WHATWG Wiki - User contributions [en]

Band names

2017-01-18T09:17:38Z

Hsivonen: http://logs.glob.uno/?c=freenode%23whatwg&s=18+Jan+2017&e=18+Jan+2017#c1017379

These are band names collected from #whatwg.

* Bogus DOM
* The Unpaired Surrogates
* Lone Surrogates
* The Designated Experts
* Spidermonkey and the GC Jitters
* Polyglot Heartbeat
* Extant Web Corpus
* Ambushed by Ambiguity
* Ambiguous Ampersands
* bad value robot
* Abort These Steps
* Shadow Piercing Descendant Combinator
* Drowning in Hypotheticals
* Radical Glyphs

== Album titles ==

* The Last Unambiguous Integer
* User Bang Important Rule
* Polygoat
* MetaExtension and Dublin Core - Live at WHATWG

Validator.nu validator-tester.py

2014-11-21T08:44:34Z

Hsivonen: s/http/https/

<code>python validator-tester.py ''config'' ''command'' ''command-arguments''</code>

See [[Validator.nu Full-Stack Tests]]

==''config''==

The following configuration parameters are available:

===--db=''filename''===

Specifies the name of the database file. Defaults to <code>db.json</code> in the current working directory.

===--service=''URI''===

Specifies the root URI of the service to be tested. Defaults to <code>https://html5.validator.nu/</code>.

==''command''==

===dumpref===

Dumps the reference data for a URI from the database into a JSON file.

Takes two arguments: URI and file name.

===dumpuri===

Dumps the result data for a URI as reported by the remote service into a JSON file.

Takes two arguments: URI and file name.

===adduri===

Adds the remote service output for a URI into the database.

Takes one argument: URI

===deluri===

Deletes the reference data for a URI from the database.

Takes one argument: URI

===checkuri===

Compare the service output for a URI against the reference data for the same URI in the database and print discrepancies.

Takes one argument: URI

===checkall===

Runs checkuri for each URI recorded in the database.

Takes no arguments.

===mergedb===

Reads an external database file (e.g. one written by dumpref) and adds the entries to the reference database overwriting existing entries in the case of key overlap.

Takes one argument: file name

==''command-arguments''==

The arguments to the command as documented for each command.

[[Category:Validator.nu Documentation]]

Validator.nu Unit Tests

2014-11-21T08:43:58Z

Hsivonen: s/Google code/GitHub/

Validator.nu has various places for unit tests.

==html5lib Tokenizer Tests==

The tokenizer of the Validator.nu HTML Parser is tested using the [https://github.com/html5lib/html5lib-tests/tree/master/tokenizer tokenizer tests] hosted by the html5lib project. <code>nu.validator.htmlparser.test.TokenizerTester</code> is the test harness.

==html5lib Tree Builder Tests==

The tree builder of the Validator.nu HTML Parser is tested using the [https://github.com/html5lib/html5lib-tests/tree/master/tree-construction tree construction tests] hosted by the html5lib project. <code>nu.validator.htmlparser.test.TreeTester</code> is the test harness.

==html5lib Encoding Tests==

The meta sniffer of Validator.nu HTML Parser used to be tested using the [https://github.com/html5lib/html5lib-tests/tree/master/encoding encoding tests] hosted by the html5lib project. <code>nu.validator.htmlparser.test.EncodingTester</code> is the test harness. ''However, both the tests and the code are out of sync with the spec.''

==WHATTF Schema Tests==

Some aspects of the validation layer are tested using the test suite the WHATTF HTML5 schemas. <code>org.whattf.syntax.Driver.java</code> is the test harness. ''These tests were written when HTML5 still had the concept strict inline / structured inline / block. Also the tests elicit more than one error per test file. The test have not been properly updated to test newer aspects of the HTML5 spec.''

==Full-stack tests==

There is a [[Validator.nu validator-tester.py|test harness]] for [[Validator.nu Full-Stack Tests|full-stack]] (well, full-stack with JSON output—not HTML output) testing.

[[Category:Validator.nu Documentation]]

Validator.nu Textarea Input

2014-11-21T08:41:52Z

Hsivonen: s/http/https/

To use [[Validator.nu Web Service Interface|Validator.nu as a Web service]] by POSTing a text field, the client issues an HTTP request either to <code>https://validator.nu/</code> or <code>https://html5.validator.nu/</code> using the POST method with an <code>multipart/form-data</code> entity body. (<code>application/x-www-form-urlencoded</code> is ''not'' supported.) [[Validator.nu Common Input Parameters|Common parameters]] are encoded as form fields. The document to check is included as the value of a form field called <code>content</code>. The <code>content</code> field must be the last field in the submission.

The request should set the <code>parser</code> parameter explicitly. <code>Content-Type</code> is synthetized by selecting <code>text/html</code> or <code>application/xml</code> depending on the <code>parser</code> value and clamping the <code>charset</code> MIME type parameter to <code>utf-8</code>).

All field values including the document source must decode as UTF-8.

==See also==
*[[Validator.nu Web Service Interface]]

[[Category:Validator.nu Documentation]]

Validator.nu Templates

2014-11-21T08:41:31Z

Hsivonen: s/http/https/

The HTML and XHTML outputs of Validator.nu are produced using SAX serializers. When variable content is pushed to the serializers, SAX events are emitted from hand-written Java code. However, for static boilerplate parts, generated code is used.

It is particularly noteworthy that for (X)HTML, the <code>MessageEmitter</code> subclass generates a document fragment that appears inside a larger document but for the other output formats, the entire response is generated by the <code>MessageEmitter</code> subclass. This design is mainly due to the legacy of controller code evolution from an initial interactive HTML-only design to cover non-interactive Web service response formats later.

==The Generator Tool==

The generated code is produced from XML file using [https://hsivonen.fi/saxcompiler/ SaxCompiler], which was written to aid the development of Validator.nu.

SaxCompiler turns an XML document into a Java class with a re-entrant static method for replaying the SAX events of the XML document. The events for the document and root element start/end can optionally be omitted.

Callbacks to an object passed as an argument to the static method are possible and used for running code that emits the variable part of the result document.

==The Generated Emitters==

===<code>PageEmitter</code>===

This emitter generates the <code>html</code>, <code>head</code>, <code>body</code>, <code>title</code>, <code>h1</code>, <code>hr</code> and <code>p</code> (after <code>hr</code>) elements. The contents of each one involves a callback to the controller.

===<code>FormEmitter</code>===

This emitter generates the contents of the <code>form</code> element (but not the element itself which is generated using hand-written code due to variability in its attributes) in the generic facet.

===<code>Html5FormEmitter</code>===

This emitter generates the contents of the <code>form</code> element (but not the element itself which is generated using hand-written code due to variability in its attributes) in the HTML5 facet.

===<code>CharsetEmitter</code>===

Emits the table row containing the character encoding override UI widget.

===<code>NsFilterEmitter</code>===

Emits the table row containing the namespace filter UI widget.

===<code>StatsEmitter</code>===

Emits the execution time statistics paragraph.

==Callbacks==

In general, all package-private methods on the controller classes (<code>VerifierServletTransaction</code> and <code>Html5ConformanceCheckerTransaction</code>) are callbacks of some kind.

[[Category:Validator.nu Documentation]]

Validator.nu POST Body Input

2014-11-21T08:40:39Z

Hsivonen: s/http/https/

To use [[Validator.nu Web Service Interface|Validator.nu as a Web service]] by POSTing an entity body, the client issues an HTTP request either to <code>https://validator.nu/</code> or <code>https://html5.validator.nu/</code> using the POST method. The document to check is included as the entity body of the request. The <code>Content-Type</code> request header must be used to communicate the MIME type of the entity body. [[Validator.nu Common Input Parameters|Common parameters]] are encoded as query string parameters.

Only <code>&</code> is supported as a query parameter separator. <code>;</code> is not supported.

Percent-encoded octets in the query string must decode to UTF-8.

==See also==
*[[Validator.nu Web Service Interface]]

[[Category:Validator.nu Documentation]]

Validator.nu parser

2014-11-21T08:40:06Z

Hsivonen: s/http/https/

The [https://about.validator.nu/htmlparser/ Validator.nu HTML parser] is an implementation of the HTML5 parsing algorithm in Java with SAX, XOM and DOM interfaces.

The code is available from
<pre>hg clone https://hg.mozilla.org/projects/htmlparser/</pre>

More information from hsivonen at #whatwg.

[[Category:Implementations]]
[[Category:Validator.nu Documentation]]

Validator.nu JSON Output

2014-11-21T08:39:40Z

Hsivonen: s/http/https/

Italicized words, such as ''object'', refer to JSON data types. “The <code>"foo"</code> ''datatype''” refers to an object of type ''datatype'' that is the value associated with the key <code>"foo"</code> in the parent ''object''.

==Media Type==

The Internet media type for this format is <code>application/json</code>. (Unless the callback extension is used, in which case the media type is <code>application/javascript</code>.)

==Root Object==

The root object is a JSON ''object''. It has one mandatory key, <code>"messages"</code>, and three optional keys, <code>"url"</code>, <code>"source"</code> and <code>"parseTree"</code>.

The values for these keys are described below.

===The <code>"messages"</code> ''array''===

The this ''array'' is an ordered collection of zero or more message ''object''s.

====Message ''object''s====

A message ''object'' has one mandatory key, <code>"type"</code>, and seven optional keys, <code>"subtype"</code>, <code>"message"</code>, <code>"extract"</code>, <code>"offset"</code>, <code>"url"</code>, <code>"line"</code> and <code>"column"</code>.

=====The <code>"type"</code> ''string''=====

The <code>"type"</code> ''string'' denotes the general class of the message. The permissible values are <code>"info"</code>, <code>"error"</code> and <code>"non-document-error"</code>.

<CODE>"info"</CODE>
means an informational message or warning that does not affect the validity of
the document being checked. <CODE>"error"</CODE> signifies
a problem that causes the validation/checking to fail. <CODE>"non-document-error"</CODE>
signifies an error that causes the checking to end in an indeterminate state because
the document being validated could not be examined to the end. Examples of such errors include broken schemas, bugs in the validator and IO errors. (Note that when a schema has parse errors, they are first reported as <CODE>error</CODE>s and then a catch-all <CODE>non-document-error</CODE> is also emitted.)

=====The <code>"subtype"</code> ''string''=====

The permissible value with <CODE>"type":"info"</CODE> is <CODE>"warning"</CODE>, which means that the message seeks to warn about the user of a formally conforming but in some way questionable issue. Otherwise, the message is taken to generally informative.

The permissible value with <CODE>"type":"error"</CODE> is <CODE>"fatal"</CODE>, which means that the error is an XML well-formedness error or, in the case of HTML, a condition that the implementor has opted to treat analogously to XML well-formedness errors (e.g. due to usability or performance considerations). Further errors are suppressed after a fatal error. In the absence of the <CODE>"subtype"</CODE> key, a <CODE>"type":"error"</CODE> message means a spec violation in general.

Permissible values with <CODE>"type":"non-document-error"</CODE> are: <CODE>"io"</CODE> (signifies an
input/output error), <CODE>"schema"</CODE> (indicates that
initializing a schema-based validator failed) and <CODE>"internal"</CODE>
(indicates that the validator/checker found an error bug in itself,
ran out of memory, etc., but was still able to emit a message). In the absence of the <CODE>"subtype"</CODE> key, a <CODE>"type":"non-document-error"</CODE> message means a problem external to the document in general.

=====The <code>"message"</code> ''string''=====

The <code>"message"</code> ''string'' represents a paragraph of text (suitable for rendering to the user as plain text without further processing) that is the message stated succinctly in natural language.

=====The <code>"extract"</code> ''string''=====

The <code>"extract"</code> ''string'' represents an extract of the document source from around the point in source designated for the message by the <code>"line"</code> and <code>"column"</code> ''number''s.

=====The <code>"offset"</code> ''number''=====

The <code>"offset"</code> ''number'' is an UTF-16 code unit index into the <code>"extract"</code> ''string''. The index identifies the same UTF-16 code unit in the extract that the <code>"line"</code> and <code>"column"</code> ''number''s identify in the full source. The first code unit has the index <code>0</code>.

=====The <code>"url"</code> ''string''=====

The <code>"url"</code> ''string'', if present, must contain the URI
(not IRI) of the resource with which the message is associated
or the literal string “<CODE>data:…</CODE>” (the last character
is U+2026) to signify that the message is associated with a data URI
resource but the exact URI has been omitted. (If a client application
wishes to show IRIs to human users, it is up to the client
application to convert the URI into an IRI.)

If the <code>"url"</code> ''string'' is absent on the message element but present on the root element, the message is considered to be associated with the resource designated by the attribute on the root element.

=====The <code>"firstLine"</code>, <code>"firstColumn"</code>, <code>"lastLine"</code> and <code>"lastColumn"</code> ''number''s=====

The <code>"firstLine"</code>, <code>"firstColumn"</code>, <code>"lastLine"</code> and <code>"lastColumn"</code> ''number''s indicate a range of source code associated with the message. The line and column numbers are one-based. The first line is line 1. The first column is column 1. Columns are counted by UTF-16 code units. A line break is considered to occupy the last column on the line it terminates.

The source lines and columns are approximate. For example, if a
message is related to an attribute, the line and column may point to
the first character if the start tag, the character after the start
tag or to the attribute inside the tag depending on implementation.
If a message is related to character data, the line and column may be
inaccurate within a run of text e.g. due to buffering.

The <code>"lastLine"</code> ''number'' indicates the last line (inclusive) onto which the source range associated with the message falls.

The <code>"firstLine"</code> ''number'' indicates the first line onto which the source range associated with the message falls. If the attribute is missing, it is assumed to have the same value as <code>"lastLine"</code>.

The <code>"lastColumn"</code> ''number'' indicates the last column (inclusive) onto which the source range associated with the message falls on the last line onto which is falls.

The <code>"firstColumn"</code> ''number'' indicates the first column onto which the source range associated with the message falls on the first line onto which is falls.

===The <code>"url"</code> ''string''===

The <code>"url"</code> ''string'', if present, must containt the URI
(not IRI) of the document being checked
or the literal string “<CODE>data:…</CODE>” (the last character
is U+2026) to signify that the message is associated with a data URI
resource but the exact URI has been omitted. (If a client application
wishes to show IRIs to human users, it is up to the client
application to convert the URI into an IRI.)

====The <code>"type"</code> ''string''====

<CODE>"success"</CODE>, <CODE>"failure"</CODE> or <CODE>"indeterminate"</CODE> for valid, invalid or inability to finish, respectively.

====The <code>"message"</code> ''string''====

A human-readable string describing the result.

===The <code>"source"</code> ''object''===

A <code>"source"</code> ''object'' has one mandatory key, <code>"code"</code>, and two optional keys, <code>"type"</code> and <code>"encoding"</code>.

====The <code>"code"</code> ''string''====

The <code>"code"</code> ''string'' represents the source of the checked document as decoded to Unicode lone surrogates replaced with the REPLACEMENT CHARACTER and with line breaks replaced with U+00A0 LINE FEED.

====The <code>"type"</code> ''string''====

The <code>"type"</code> ''string'' represents the media type of the input without parameters.

====The <code>"encoding"</code> ''string''====

The <code>"encoding"</code> ''string'' represents the <code>charset</code> media type parameter of the input.

===The <code>"parseTree"</code> ''object''===

What to put here? [https://simon.html5.org/specs/sdf SDF]?

==Example==

<pre><nowiki>{
"url": "http://example.org/",
"messages": [
{
"type" : "info",
"subtype": "warning",
"lastLine" : 20,
"lastColumn" : 15,
"url" : "http://example.com/",
"message": "Trailing slash for void element",
"extract": " ",
"hiliteStart" : 3,
"hiliteLength" : 1
},
{
"type" : "error",
"subtype": "fatal",
"lastLine" : 42,
"lastColumn" : 17,
"url" : "http://example.com/",
"message": "Missing end tag for the “foo” element"
}
],
"source": {
"code" : "...",
"type" : "text/html",
"encoding": "UTF-8"
},
"parseTree": {
...
}
}</nowiki></pre>

==Processing Model==

Clients that consume the message format are referred to as
processors. They must use a parser conforming to [https://tools.ietf.org/html/rfc4627 RFC 4627] to parse the
format.

If the root is not an ''object'' with the key <CODE>"messages"</CODE>,
the JSON text is deemed to be in an unknown format and not processable
according to this processing model.

If the processor encounters a key–value pair in an ''object'' with a known key and an unknown value where a value enumerated in this specification is expected, the processor must ignore the key–value pair. If a processor encounters an ''object'' that is missing a required key (possibly because it was ignored under the previous rule), the processor must ignore the entire ''object''. If a message ''object'' does not have a
<CODE>"line"</CODE> ''number'' with a permissible value, a <CODE>"column"</CODE>
''number'' on the ''object'' must be ignored if present.

Processors must process the items in a way that is consistent with
the semantics of the items.

===Determining Outcome===

The outcome of the validation process may be success, failure or indeterminate.

# If there are one or more <CODE>non-document-error</CODE> messages, the outcome is indeterminate.
# Else if there are one or more <CODE>error</CODE> messages, the outcome is failure.
# Else the outcome is success.

==Callback==

The format described here may [[Validator.nu Common Input Parameters#callback|optionally be wrapped in a JavaScript function call]].

==See also==
*[[Validator.nu Web Service Interface]]

[[Category:Validator.nu Documentation]]

Validator.nu GNU Output

2014-11-21T08:38:18Z

Hsivonen: s/http/https/

This format is an adaptation of the [https://www.gnu.org/prep/standards/standards.html#Errors GNU error format].

==Media Type==

This format has semantics beyond the semantics of <code>text/plain</code>. However, for compatibility and given the lack of a specific media type, this format uses the media type <code>text/plain; charset=utf-8</code>.

==Character Encoding==

This format is defined in terms of Unicode characters. For transport as bytes, the Unicode characters are encoded as UTF-8.

==General Format==

The format consists of messages represented as text lines.

Each line consists of the URI of the file that the message pertains to, U+003A COLON, optionally a position descriptor, U+003A COLON if there was a position descriptor, U+0020 SPACE, type descriptor, U+003A COLON, U+0020 SPACE, message and U+000A LINE FEED.

When there are no lines, there are characters—not even a single U+000A LINE FEED.

==URI of the File==

The URI of the file is its IRI converted to the URI form with U+0022 QUOTATION MARK before and after or nothing (not even quotes) if the IRI of the document is not available. (Literal U+0022 QUOTATION MARK never appears in the URI. <code>%22</code> may appear instead.)

==Position Descriptor==

The position descriptor indicates the source position that the message pertains to in terms of lines and columns. The first line is line number 1. The first character on a line occupies column number 1. Columns are counted as UTF-16 code units without tab expansion. (The GNU spec doesn't specify how non-ASCII is counted and specifies tab expansion to stops at every 8 columns.)

The position descriptor takes one of these formats:

* ''line number''
* ''line number'', U+002E FULL STOP, ''column number''
* ''start line number'', U+002D HYPEN-MINUS, ''end line number''
* ''start line number'', U+002E FULL STOP, ''start column number'', U+002D HYPEN-MINUS, ''end line number'', U+002E FULL STOP, ''end column number''

Start and end are inclusive. The numbers consist of one or more characters in the range from U+0030 DIGIT ZERO to U+0039 DIGIT NINE interpreted as a decimal number.

==Type Descriptor==

The type descriptor consists of a supertype descriptor optionally followed by U+0020 SPACE and a subtype descriptor.

The supertype descriptor denotes the general class of the message. The permissible values are <code>info</code>, <code>error</code> and <code>non-document-error</code>.

<CODE>info</CODE>
means an informational message or warning that does not affect the validity of
the document being checked. <CODE>error</CODE> signifies
a problem that causes the validation/checking to fail. <CODE>non-document-error</CODE>
signifies an error that causes the checking to end in an indeterminate state because
the document being validated could not be examined to the end. Examples of such errors include broken schemas, bugs in the validator and IO errors. (Note that when a schema has parse errors, they are first reported as <CODE>error</CODE>s and then a catch-all <CODE>non-document-error</CODE> is also emitted.)

When the supertype descriptor is <CODE>info</CODE> the permissible value for the subtype descriptor is <CODE>warning</CODE>, which means that the message seeks to warn about the user of a formally conforming but in some way questionable issue. Otherwise, the message is taken to generally informative.

When the supertype descriptor is <CODE>error</CODE> the permissible value for the subtype descriptor is <CODE>fatal</CODE>, which means that the error is an XML well-formedness error or, in the case of HTML, a condition that the implementor has opted to treat analogously to XML well-formedness errors (e.g. due to usability or performance considerations). Further errors are suppressed after a fatal error. In the absence of the <CODE>"subtype"</CODE> key, a <CODE>"type":"error"</CODE> message means a spec violation in general.

When the supertype descriptor is <CODE>non-document-error</CODE> the permissible value for the subtype descriptor are <CODE>io</CODE> (signifies an
input/output error), <CODE>schema</CODE> (indicates that
initializing a schema-based validator failed) and <CODE>internal</CODE>
(indicates that the validator/checker found an error bug in itself,
ran out of memory, etc., but was still able to emit a message). In the absence of the subtype descriptor key, a <CODE>non-document-error</CODE> message means a problem external to the document in general.

==Message==

The message is a human-readable string that does not contain U+000A LINE FEED or U+000D CARRIAGE RETURN. It may be the empty string. ([[Validator.nu Common Input Parameters#asciiquotes|ASCII quotes can be requested]].)

==Processing Model==

Clients that consume the message format are referred to as
processors.

If the input contains a line that is not in the format described above, the input is deemed to be in an unknown format and not processable according to this processing model.

For forward compatibility, processors must treat unknown subtype descriptors as if there were no subtype descriptor when deciding the semantics according to the previous paragraphs.

Processors must process the lines in a way that is consistent with
the semantics of the lines.

===Determining Outcome===

The outcome of the validation process may be success, failure or indeterminate.

# If there are one or more <CODE>non-document-error</CODE> messages, the outcome is indeterminate.
# Else if there are one or more <CODE>error</CODE> messages, the outcome is failure.
# Else the outcome is success.

Note that <code>info</code> messages can be suppressed with by setting the input parameter [[Validator.nu Common Input Parameters#level|<code>level</code>]] to <code>error</code> in which case success is equivalent to this format containing no lines.

==See also==
*[[Validator.nu Web Service Interface]]

[[Category:Validator.nu Documentation]]

Validator.nu GET Input

2014-11-21T08:37:33Z

Hsivonen: s/http/https/

To use [[Validator.nu Web Service Interface|Validator.nu as a Web service]] via GET, the client issues an HTTP request either to <code>https://validator.nu/</code> or <code>https://html5.validator.nu/</code> using the GET method. The IRI (<code>http</code> or <code>https</code>.) of the document to check is encoded as a query string parameter called <code>doc</code>. [[Validator.nu Common Input Parameters|Common parameters]] are also encoded as query string parameters.

Only <code>&</code> is supported as a query parameter separator. <code>;</code> is not supported.

Percent-encoded octets in the query string must decode to UTF-8.

==See also==
*[[Validator.nu Web Service Interface]]

[[Category:Validator.nu Documentation]]

Validator.nu Full-Stack Tests

2014-11-21T08:37:02Z

Hsivonen: s/http/https/; s/hsivonen.iki.fi/hsivonen.com/

Validator.nu has a framework for doing full-stack HTML5 validator testing in an implementation-independent manner. Currently, the framework is lacking tests.

The framework implements the design discussed at the HTML WG unconference session on validator testing at TPAC 2007.

==The Front End==

The front end for the system is the script named <code>validator-tester.py</code> in the <code>test-harness/</code> directory of the <code>validator</code> SVN module. The script requires a recent version of [https://pypi.python.org/pypi/simplejson simplejson].

The script is documented on [[Validator.nu validator-tester.py|a separate page]].

==The General Idea==

The idea is to test the full validator through a Web service API in order to test the aggregation of software components running together with a realistic configuration. Testing merely the parser or the validation layer risks testing them in a different configuration than what gets deployed and without a real HTTP client connecting to real HTTP server.

The tests are intended to be implementation-independent for two reasons:
# to make the tests reusable for different products
# to avoid clamping down the implementation details within a product

There's no cross-product way to give identifiers to HTML5 errors. For example, the identification of errors pertaining to element nesting would be different in a grammar-based implementation and in an assertion-based implementation. Moreover, with grammar-based implementations, only the first error is reliable.

Therefore, the testing framework does not test for error identity. It only tests that the first error elicited by a test case falls within a specified source code character range. (This assumes that implementations can report error location, which is a bad assumption for validators that validate the DOM inside a browser, but we’d be left with no useful assumptions without this one.)

Thus, a test suite consists of files on a public HTTP server and a reference database of URIs pointing to the tests and expected locations of the first error for each URI.

==Writing a Test Eliciting an Error==

===Identifying a Testable Conformance Criterion===

First, a testable assertion needs to be identified. For example: “The ampersand must be followed by one of the names given in the named character references section, using the same case.”

===Writing a Test Violationg the Conformance Criterion===

The test document should have a violation of the previously identified conformance criterion as its first error. Preferably, this error should be the only error in the document.

We can go read the list of named characters and come up with a test document like this:
<pre><!DOCTYPE html>
<html>
<head>
<title>Unescaped ampersand</title>
</head>
<body>
&amgueao
There should be an error.
</body>
</html></pre>

Note that a test that isn’t testing the doctype or tag inference should have the doctype and explicit tags for <code>html</code>, <code>head</code>, <code>title</code> and <code>body</code> in order to avoid accidentally testing something related to tag inference. It is a good idea to make the content of
<code>title</code> hint at what is being tested and include a paragraph saying whether an error is expected or not.

===Placing the Test Case on a Server===

Next, the test file needs to be put on an HTTP server. If you are not testing the internal encoding declaration, the absence of an encoding declaration or a particular encoding, you should serve the file with the header <code>Content-Type: text/html; charset=utf-8</code> (or <code>Content-Type: application/xhtml+xml</code> for XHTML5 tests).

In this case, the sample test has the URI [http://hsivonen.com/test/moz/unescaped-ampersand.html <code><nowiki>http://hsivonen.com/test/moz/unescaped-ampersand.html</nowiki></code>].

===Generating a Reference Result===

If this is a regression test (i.e. a check for the error has already been implemented in Validator.nu), the reference result can be generated using Validator.nu.

First, use the [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Funescaped-ampersand.html HTML UI to check] that the right error is given and that the right piece of source is highlighted.

Then, use <code>validator-tester.py</code> to dump the result in a JSON file:
<pre>python validator-tester.py dumpuri http://hsivonen.com/test/moz/unescaped-ampersand.html temp.json</pre>

You can then open the temporary file in your favorite text editor:
<pre>edit temp.json</pre>

You should see contents like this:
<pre>{
"http://hsivonen.com/test/moz/unescaped-ampersand.html": [
{
"firstColumn": 7,
"firstLine": 7,
"lastColumn": 7,
"lastLine": 7,
"message": "Text after \u201c&\u201d did not match an entity name. Probable cause: \u201c&\u201d should have been escaped as \u201c&\u201d."
}
]
}</pre>

The outmost JSON object has a single key-value pair with the URI as the key and an array of errors as the value. In this case, the array has only one element. If it had more, the rest of the elements would be merely informative for a human and would be ignored by the test harness when comparing results.

The error is a JSON object that has five keys. Four for the error range and one for the message. The message is merely informative for humans. It isn’t compared by the test harness.

In this case, the first character of the error range is on column 7 on line 7 (inclusive), and the last character of the range is on column 7 on line 7 (inclusive). The first line is line 1. The first column is column 1. The columns are counted by UTF-16 code unit. The lines are separated by CR, LF, or CRLF.

Validator.nu highlights only a single character. This is an implementation detail, however. It is reasonable for an implementation to locate the error a bit more broadly. In general, if an error occurs in a tag, the error range should cover the whole tag and if an error occurs in a text node, the range should cover the text node plus the following <code><</code> character.

Edit the range to start 3 column earlier and end 5 columns later:
<pre>{
"http://hsivonen.com/test/moz/unescaped-ampersand.html": [
{
"firstColumn": 4,
"firstLine": 7,
"lastColumn": 12,
"lastLine": 7,
"message": "Text after \u201c&\u201d did not match an entity name. Probable cause: \u201c&\u201d should have been escaped as \u201c&\u201d."
}
]
}</pre>

For an implementation to pass the test, it must report at least one error and the location of the first error must fall within this range.

Now you can save the file and commit the modified file into the reference database:
<pre>python validator-tester.py mergedb temp.json</pre>

When the autogenerated reference does not need editing, you can use this shortcut:
<pre>python validator-tester.py adduri http://hsivonen.com/test/moz/en-UK.html</pre>

==Writing a Test Eliciting No Errors==

When writing a test case that is expected to pass without errors, you need to write it and put in on the server as above. However, since there is nothing to edit in the reference results, you can always use the <code>adduri</code> shortcut command mentioned above.

==Running a Test==

You can run the test created above with this command:
<pre>python validator-tester.py checkuri http://hsivonen.com/test/moz/unescaped-ampersand.html</pre>

There is no output if the test passes.

==Running All Tests==

To run all tests that have reference results in the database, run:
<pre>python validator-tester.py checkall</pre>

[[Category:Validator.nu Documentation]]

Validator.nu Form Upload Input

2014-11-21T08:35:19Z

Hsivonen: s/http/https/

To use [[Validator.nu Web Service Interface|Validator.nu as a Web service]] by form-based file upload:

* the client issues an HTTP request either to <code>https://validator.nu/</code> or <code>https://html5.validator.nu/</code>

* the request uses the POST method with an <code>multipart/form-data</code> entity body

* [[Validator.nu Common Input Parameters|common parameters]] are encoded as form fields

* the document to check is included as the value of a file upload field called <code>file</code>

* '''the <code>file</code> field must be the last field in the submission'''

Since the <code>Content-Type</code> supplied by browsers for the uploaded file is unreliable, the client-supplied <code>Content-Type</code> is overridden with a synthetic <code>Content-Type</code> if the filename is supplied ''and'' it has a well-known extension. The well-known extensions are <code>html</code>, <code>htm</code>, <code>xhtml</code>, <code>xht</code>, <code>atom</code>, <code>rng</code>, <code>xsl</code>, <code>xml</code> and <code>dbk</code>.

The parameter field values must decode as UTF-8.

==See also==
*[[Validator.nu Web Service Interface]]

[[Category:Validator.nu Documentation]]

Category:Validator.nu Documentation

2014-11-21T08:34:38Z

Hsivonen: s/http/https/

Documentation for [https://validator.nu/ Validator.nu].

MicrosyntaxDescriptions

2014-11-21T08:29:50Z

Hsivonen: Migrate links to https

The purpose of this page is to enable collaborative creation of brief advisory text for each HTML5 microsyntax so that when the content of an attribute value or the text content of an element does not conform to a given microsyntax, a validator can display the advisory text about the syntax to guide the author to fix the content. Note that like the rest of this wiki, editing requires you to agree to release your contributions under the MIT license (see wiki footer). Please note that while copying text from the [https://html.spec.whatwg.org/ WHATWG version of HTML 5] is OK, copying text from RFCs or W3C specs is not OK.

Note that some formats pertain to Web Forms 2.0 (e.g. <code>datetime-local</code>).

Please keep descriptions short: one paragraph in length.

==a-rel==
A whitespace-separated list of link types, with no duplicate keywords in the list. Each link type must be listed as allowed on <code><a></code> and <code><area></code> in the [https://html.spec.whatwg.org/multipage/links.html#linkTypes HTML specification], or must be listed as allowed on <code><a></code> and <code><area></code> on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki], or must be an absolute URL. You can register link types on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki] yourself.

==browsing-context==
A browsing context name is any string that does not start with an underscore (<code>_</code>).

==browsing-context-or-keyword==
A browsing context name or keyword is either any string that does not start with an underscore (<code>_</code>) or a string that case-insensitively matches one of: <code>_blank</code>, <code>_self</code>, <code>_parent</code>, or <code>_top</code>.

==cdo-cdc-pair==
Any text content that does not contain the character sequence "<code></code>".

==charset==
An preferred encoding name according to the [http://encoding.spec.whatwg.org/ Encoding Standard]. Example: <code>utf-8</code>

==charset-list==
A whitespace-separated list of preferred encoding names according to the [https://encoding.spec.whatwg.org/ Encoding Standard]. Example: <code>utf-8 windows-1252</code>

==circle==
A circle is specified as three comma-separated (no spaces allowed) integers the last one of which is non-negative. An integer consists of one or more digits (<code>0</code>–<code>9</code>), optionally preceded by a hyphen (<code>-</code>). Examples of circles: <code>5,5,10</code> and <code>-5,0,20</code>

==date==
A date in the form <code>YYYY-MM-DD</code>. Example: <code>2002-09-29</code>.

==date-or-time==
A [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-date-or-time-string date or time string]; that is, one of the following:
a date, which must be in the form <code>YYYY-MM-DD</code> • or, a time, which must begin in the form <code>hh:mm</code>, and can optionally be followed by <code>:ss</code>, which in turn can optionally be followed by “<code>.</code>” and one or more digits • or, a date, followed by “<code>T</code>”, followed by a time, followed by time-zone information, which must be either “<code>Z</code>”, or in the form <code>+hh:mm</code> or the form <code>-hh:mm</code> • Examples: <code>1996-01-01</code>, <code>12:05:25</code>, <code>1996-01-01T12:05:25-02:00</code>, <code>1996-01-01T12:05:25.6</code> • Note: The validator currently allows some values that the HTML specification prohibits; for example, it allows <code>1996-01-01T12:05:25</code> (a date and time with no time-zone information) and <code>12:05:25Z</code> (a time with no date but with time-zone information).

==datetime==
An ISO 8601 date and time in the UTC time zone, i.e. <code>YYYY-MM-DDThh:mm</code> optionally followed by <code>:ss</code> for the seconds, optionally followed by <code>.</code> and one, two, or three digits for the fraction of a second, and finally followed by <code>Z</code>. Examples: <code>1996-01-01T12:05Z</code>, <code>1996-01-01T12:05:25.6Z</code>.

==datetime-local==
An ISO 8601 date and time with no time zone information, i.e. <code>YYYY-MM-DDThh:mm</code> optionally followed by <code>:ss</code> for the seconds, optionally followed by <code>.</code> and one or more digits for the fraction of a second. Examples: <code>1996-01-01T12:05</code>, <code>1996-01-01T12:05:25.6</code>.

==datetime-tz==
A [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-global-date-and-time-string global date and time string]; that is, a date, followed by a “<code>T</code>” or a single space, followed by a time, followed by time-zone information, where: the date must be in the form <code>YYYY-MM-DD</code> • the time must begin in the form <code>hh:mm</code>, followed by <code>:ss</code>, optionally followed by “<code>.</code>” and one, two, or three or digits • the time-zone information must be either “<code>Z</code>” or in the form <code>+hh:mm</code> or the form <code>-hh:mm</code> • Examples: <code>1996-01-01T12:05:25-02:00</code>, <code>1996-01-01T12:05:25Z</code>



==email==
An e-mail address must match the <code>addr-spec</code> production defined in [https://tools.ietf.org/html/rfc2822#section-3.4.1 RFC 2822 section 3.4.1] excluding the <code>CFWS</code> production everywhere and excluding the <code>FWS</code> production everywhere except in the <code>quoted-string</code> production.

==float==
First, optionally, <code>-</code> (U+002D). Then, a series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, a single <code>.</code> (U+002E) followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. For example, <code>-42.42E+42</code> is valid but <code>.5</code> or <code>+2</code> are not.

==float-non-negative==
A series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, a single <code>.</code> (U+002E) followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. Or, alternatively to the foregoing: First, <code>-</code> (U+002D). Then, a series of one or more zeros. Then, optionally, a single <code>.</code> (U+002E) followed by one or more zeros. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. For example, <code>42.42E+42</code> and <code>-000.000</code> are valid but <code>.5</code> or <code>-0.01</code> are not.

==float-positive==
A series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, a single <code>.</code> (U+002E) followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. One of the digits so far has to be non-zero. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. For example, <code>42.42E+42</code> is valid but <code>0.0</code> or <code>-2</code> are not.

==hash-name==
A <code>#</code> (number sign) character followed by any string.

==ID==
An ID consists of at least one character but must not contain any whitespace.

==image-candidate-strings==
A comma-separated list of strings, each of which consists of a URL optionally followed by either a pixel density descriptor or a width descriptor.

==image-candidate-strings-width-required==
A comma-separated list of strings, each of which must consist of a URL followed by a width descriptor.

==integer==
One or more digits (<code>0</code>–<code>9</code>), optionally preceded by a hyphen (<code>-</code>). For example: <code>42</code> and <code>-273</code> are valid, but <code>+42</code> is not.

==integer-non-negative==
One or more digits (<code>0</code>–<code>9</code>). For example: <code>42</code> and <code>0</code> are valid, but <code>-273</code> is not.

==integer-positive==
One or more digits (<code>0</code>–<code>9</code>), with at least one which is non-zero. For example: <code>42</code> is valid, but <code>00</code> is not.

==iri==
An absolute URL. For example: <code><nowiki>http://</nowiki>example.org/hello</code>, but not <code>/hello</code>. Spaces should be escaped as <code>%20</code>.

==iri-ref==
Any URL. For example: <code>/hello</code>, <code>#canvas</code>, or <code><nowiki>http://</nowiki>example.org/</code>. Characters should be represented in [http://www.macchiato.com/unicode/nfc-faq NFC] and spaces should be escaped as <code>%20</code>.

==language==
An [https://tools.ietf.org/html/rfc5646 RFC 5646] language tag consists of hyphen-separated ASCII-alphanumeric subtags. There is a primary tag identifying a natural language by its shortest ISO 639 language code (e.g. <code>en</code> for English) and zero or more additional subtags adding precision. The most common additional subtag type is a region subtag which most commonly is a two-letter ISO 3166 country code (e.g. <code>GB</code> for the United Kingdom). IANA maintains a [https://www.iana.org/assignments/language-subtag-registry registry of permissible subtags].

==link-rel==
A whitespace-separated list of link types listed as allowed on <code><link></code> in the [https://html.spec.whatwg.org/multipage/links.html#linkTypes HTML specification] or listed as an allowed on <code><link></code> on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki] without duplicate keywords in the list. You can register link types on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki] yourself.

==media-query==
One or more media queries, combined in a comma-separated list. Each media query consists of a '''media type''' and zero or more expressions that check for the conditions of particular '''media features'''. A media type is one of the following: '''all''', '''braille''', '''embossed''', '''handheld''', '''print''', '''projection''', '''screen''', '''speech''', '''tty''', or '''tv'''. ''Note: The '''aural''' media type is deprecated''. For information about valid media features and about the exact syntax of media queries, see the [https://drafts.csswg.org/mediaqueries3/ Media Queries] specification.

==meta-charset==
The string <code>text/html;</code>, optionally followed by whitespace, followed by <code>charset=</code>, followed by a preferred encoding name according to the [https://encoding.spec.whatwg.org/ Encoding Standard]. Example: <code>text/html; charset=utf-8</code>

==meta-name==
A metadata name listed in the [https://html.spec.whatwg.org/multipage/semantics.html#standard-metadata-names HTML specification] or listed in the [https://wiki.whatwg.org/wiki/MetaExtensions WHATWG wiki]. You can register metadata names on the [https://wiki.whatwg.org/wiki/MetaExtensions WHATWG wiki] yourself.

==mime-type==
A [https://tools.ietf.org/html/rfc2616#section-3.7 media-type as defined in RFC 2616]; that is, typically, a required ''type'', followed by a "<code>/</code>" character, followed by a required ''subtype'', optionally followed by one or more instances of a "<code>;</code>" character followed by a ''parameter''. Examples: <code>text/css</code>, <code>text/css;charset=utf-8</code>.

==mime-type-list==
(WF2)

==month==
An ISO 8601 date with year and month, i.e. <code>YYYY-MM</code>. Example: <code>2007-11</code>.

==non-empty-string==
Any string that is not the empty string.

==pattern==
(WF2)

==polyline==
...

==ratio==
(progress content)

==rectangle==
...

==script==
Any text content that does not contain the character sequence "<code></code>" and that does not contain any occurrence of the string "<code></script</code>" followed by a space character, "<code>></code>", or "<code>/</code>". For further details, see [https://html.spec.whatwg.org/multipage/scripting-1.html#restrictions-for-contents-of-script-elements Restrictions for contents of script elements].

==script-documentation==
Zero or more ''code comments'', each of which is either a single-line comment starting with "<code>//</code>" or a multi-line comment starting with "<code>/*</code>" and ending with "<code>*/</code>". The content must also meet the constraints of the [https://wiki.whatwg.org/wiki/MicrosyntaxDescriptions#script script] microsyntax. For further details, see [https://html.spec.whatwg.org/multipage/scripting-1.html#inline-documentation-for-external-scripts Inline documentation for external scripts].

==simple-color==
A string of seven characters that starts with <code>#</code> and ends with six characters each of which is <code>0</code>…<code>9</code>, <code>a</code>…<code>f</code> or <code>A</code>…<code>F</code>.

==source-size-list==
A comma-separated list of zero or more source sizes (<media-condition> <length>) optionally followed by a default size (<length>) but at least one of them.

==string-without-line-breaks==
Any string that does not contain the carriage return character or the line feed character.

==svg-pathdata==
A list of zero or more path-data expressions, where each expression consists of a one-letter command followed by numbers that serve as arguments for the command (in most cases, pairs of coordinates). Commas and/or whitespace must be used to separate the arguments for a command from one another—but '''commas must not be used to separate commands''', though whitespace can optionally be used to do so. Examples: "<code>M 100 100 L 300 100 L 200 300 z</code>" or "<code>M100,100L300,100,200,300z</code>". For more information, see the [http://www.w3.org/TR/SVG11/paths.html#PathData section on path data in the SVG 1.1 specification].

==time==
A time (hour, minute, seconds, fractional seconds) is encoded according to ISO 8601 with no time zone: two digits (<code>0</code>–<code>9</code>) for the hour, a colon, two digits for the minute, optionally a colon and two digits for the second, and optionally (if the seconds are present) a period (<code>.</code>) and one, two, or three digits for the fraction of a second. All the numbers must be in base ten and zero-padded if necessary. For instance: <code>23:59:00.000</code> or <code>00:00:05</code>.

==time-datetime==
One of the following: [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-month-string month], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-date-string date], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-yearless-date-string yearless date], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-time-string time], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-local-date-and-time-string local date and time], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-time-zone-offset-string time-zone offset], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-global-date-and-time-string global date and time], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-week-string week], [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-non-negative-integer non-negative integer], or [https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-duration-string duration]. For more information and examples, see the [https://html.spec.whatwg.org/multipage/text-level-semantics.html#datetime-value section on the datetime value in the HTML specification].

==week==
A week consists of a year and a week number encoded according to ISO 8601: four or more digits (<code>0</code>–<code>9</code>) representing the year, a hyphen (<code>-</code>), a literal <code>W</code>, and two digits for the week, zero-padded if necessary. The week number must be a number greater than or equal to <code>01</code>. Week <code>01</code> of a given year is the week containing the 4th of January; weeks start on Monday. For instance: <code>2005-W52</code> is the week that ended on Sunday the first of January, 2006.

[[Category:Validator.nu Documentation]]

Validator.nu Web Service Interface

2014-11-21T08:21:18Z

Hsivonen: s/http/https/; s/hsivonen.iki.fi/hsivonen.com/

Validator.nu can be called as a Web service. Input and output modes can be chosen completely orthogonally. Responses and requests can be optionally compressed (independently of each other).

(Please use the Web service API reasonably. See the [https://about.validator.nu/#tos Terms of Service].)

==Input Modes==

For most Web service use cases, you should probably POST the document as the HTTP entity body.

===Implemented===

* Document [[Validator.nu GET Input|URL as a GET parameter]]; the service retrieves the document by URL over HTTP or HTTPS.
* Document [[Validator.nu POST Body Input|POSTed as the HTTP entity body]]; parameters in query string as with GET.
* Document [[Validator.nu Textarea Input|POSTed as a <code>textarea</code> value]].
* Document [[Validator.nu Form Upload Input|POSTed as a form-based file upload]].

===Not Implemented===

* Document in a <CODE>data:</CODE> URI as a GET parameter.
* <code>application/x-www-form-urlencoded</code>

==Output Modes==

When using Validator.nu as a Web service back end, the [[Validator.nu XML Output|XML]] and [[Validator.nu JSON Output|JSON]] output formats are recommended for forward compatibility. The available JSON tooling probably makes consuming JSON easier. The XML format contains XHTML elaborations that are not available in JSON. Both formats are streaming, but streaming XML parsers are more readily available. XML cannot represent some input strings faithfully.

===Implemented===

* HTML with microformat-style <CODE>class</CODE> annotations (default output; should not be assumed to be forward-compatibly stable).
* XHTML with microformat-style <CODE>class</CODE> annotations (append <code>&out=xhtml</code> to URL; should not be assumed to be forward-compatibly stable).
* [[Validator.nu XML Output|XML]] (append <code>&out=xml</code> to URL).
* [[Validator.nu JSON Output|JSON]] (append <code>&out=json</code> to URL).
* [[Validator.nu GNU Output|GNU error format]] (append <code>&out=gnu</code> to URL).
* Human-readably plain text (append <code>&out=text</code> to URL; should not be assumed to be forward-compatibly stable for machine parsing—use the GNU format for that).

===Not Implemented===

* Relaxed-compatible (lacks a spec)
* Unicorn-compatible (hoping that Unicorn changes instead)
* W3C Validator-compatible SOAP (legacy)
* EARL (not implemented; domain modeling mismatch)

==Compression==

Validator.nu supports compression in order to save bandwidth.

===Request Compression===

Validator.nu supports HTTP request compression. To use it, compress the request entity body using gzip and specify <code>Content-Encoding: gzip</code> as a ''request'' header.

===Response Compression===

Validator.nu supports HTTP response compression. Please use it. Response compression is orthogonal to the input methods and output formats.

The standard HTTP gzip mechanism is used. To indicated that you prepared to handle gzipped responses, include the <code>Accept-Encoding: gzip</code> request header. When the header is present, Validator.nu will gzip compress the response. You should also be prepared to receive an uncompressed, though, since in the future it may make sense to turn off compression under heavy CPU load.

==Sample Code==

There a [https://about.validator.nu/html5check.py sample Python program] that shows how to deal with compression and redirects. (It may not be exemplary Python, though.)

==CORS Example==

You can also hit the API using [https://developer.mozilla.org/en-US/docs/HTTP_access_control CORS] over AJAX. [https://gist.github.com/gists/3902535 Basic example using jQuery].

==Sample Messages==

There are [http://hsivonen.com/test/moz/messages-types/ documents for provoking different message types].

{|
|-
! No message
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fno-message.html HTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fno-message.html&out=xhtml XHTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fno-message.html&out=xml XML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fno-message.html&out=json JSON]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fno-message.html&out=gnu GNU]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fno-message.html&out=text Text]
|-
! Info
| [https://validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Finfo.svg HTML]
| [https://validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Finfo.svg&out=xhtml XHTML]
| [https://validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Finfo.svg&out=xml XML]
| [https://validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Finfo.svg&out=json JSON]
| [https://validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Finfo.svg&out=gnu GNU]
| [https://validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Finfo.svg&out=text Text]
|-
! Warning
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fwarning.html HTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fwarning.html&out=xhtml XHTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fwarning.html&out=xml XML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fwarning.html&out=json JSON]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fwarning.html&out=gnu GNU]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fwarning.html&out=text Text]
|-
! Error (precise location)
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fprecise-error.html HTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fprecise-error.html&out=xhtml XHTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fprecise-error.html&out=xml XML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fprecise-error.html&out=json JSON]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fprecise-error.html&out=gnu GNU]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Fprecise-error.html&out=text Text]
|-
! Error (range location)
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Frange-error.html HTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Frange-error.html&out=xhtml XHTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Frange-error.html&out=xml XML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Frange-error.html&out=json JSON]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Frange-error.html&out=gnu GNU]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Frange-error.html&out=text Text]
|-
! Fatal
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Ffatal.xhtml HTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Ffatal.xhtml&out=xhtml XHTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Ffatal.xhtml&out=xml XML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Ffatal.xhtml&out=json JSON]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Ffatal.xhtml&out=gnu GNU]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2Ffatal.xhtml&out=text Text]
|-
! IO
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2F404.html HTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2F404.html&out=xhtml XHTML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2F404.html&out=xml XML]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2F404.html&out=json JSON]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2F404.html&out=gnu GNU]
| [https://html5.validator.nu/?doc=http%3A%2F%2Fhsivonen.com%2Ftest%2Fmoz%2Fmessages-types%2F404.html&out=text Text]
|}

[[Category:Validator.nu Documentation]]

Validator.nu Common Input Parameters

2014-11-21T08:17:20Z

Hsivonen: s/http/https/

Validator.nu accepts the following parameters regardless of input method. How these parameters are communicated depends on the input method.

Validator.nu has a generic facet at <code>https://validator.nu/</code> and an (X)HTML5 facet at <code>https://html5.validator.nu/</code>. Some parameters apply only to the generic facet. All parameters listed here are optional.

==Parameters for both the generic and HTML5 facets==

===<code>out</code>===

{| class="wikitable"
|-
! align="left" | Value
! align="left" | Format
|-
| ''none''
| HTML
|-
| <code>xhtml</code>
| XHTML
|-
| <code>xml</code>
| [[Validator.nu XML Output|XML]]
|-
| <code>json</code>
| [[Validator.nu JSON Output|JSON]]
|-
| <code>gnu</code>
| [[Validator.nu GNU Output|GNU error format]]
|-
| <code>text</code>
| Human-readable text (not for machine parsing)
|}

===<code>showsource</code>===

The only supported value is <code>yes</code> which means that source is shown (if supported by the output format).

===<code>level</code>===

The only supported value is <code>error</code> which means that only errors and non-document errors are reported. That is, informative messages ''including warnings'' are not reported.

===<code>nsfilter</code>===

Space-separated list of XML namespace URIs. Elements (and their children) and attributes in those namespaces are filtered out between the XML parser and the validation layer. The filtered elements participate in ID uniqueness checking. The filter doesn’t apply to HTML parser.

==Parameters for the generic facet only==

===<code>schema</code>===

This parameter takes a space-separated list of schema IRIs (<code>http</code> or <code>https</code>). The schemas can be RELAX NG 1.0 schemas, Schematron 1.5 schemas or identifiers for built-in non-schema-based checkers.

===<code>laxtype</code>===

The only supported value is <code>yes</code> which means that RFC 3023 character encoding defaults are disrespected and <code>text/html</code> is accepted as an XML MIME type.

===<code>parser</code>===

{| class="wikitable"
|-
! align="left" | Value
! align="left" | Meaning
|-
| ''none''
| Choice of HTML or XML parser is based on <code>Content-Type</code>. HTML parser configuration is based on doctype. XML parser does not load external entities.
|-
| <code>xml</code>
| XML parser, will not load external entities
|-
| <code>xmldtd</code>
| XML parser, will load external entities
|-
| <code>html</code>
| HTML parser, configuration is based on doctype.
|-
| <code>html5</code>
| HTML parser in the HTML5 mode.
|-
| <code>html4</code>
| HTML parser insisting on HTML 4.01 Strict doctype and emitting additional HTML 4 errors that are not HTML5 errors.
|-
| <code>html4tr</code>
| HTML parser insisting on HTML 4.01 Transitional doctype and emitting additional HTML 4 errors that are not HTML5 errors.
|}

==Format-Specific Parameters==

These parameters are specific to only some output formats.

===<code>asciiquotes</code>===

The only supported value is <code>yes</code> which means that ASCII quotes and apostrophes will be substituted for the Unicode smart quotes. This parameter only applies with <code>out=text</code> and <code>out=gnu</code>. The output may still contain Unicode characters in general.

===<code>callback</code>===

When this parameter is present, its value is taken to be the name of a JavaScript callback function to which the JSON object is given as an argument. This parameter only applies with <code>out=json</code>. The value must not be a JavaScript reserved word.

==See also==
*[[Validator.nu Web Service Interface]]

[[Category:Validator.nu Documentation]]

Why not conneg

2013-08-19T06:48:23Z

Hsivonen: /* Negotiating by format */ Fix typo from “can” to “can’t”, add punctuation

The purpose of this page is to explain what's wrong with HTTP content negotiation and why you should not suggest HTTP content negotiation as a solution to a problem.

HTTP content negotiation has four axes: negotiation by format (<code>Accept</code>), negotiation by character encoding <code>Accept-Charset</code>, negotiation by natural language (<code>Accept-Language</code>) and negotiation by compression (<code>Accept-Encoding</code>). These axes need to be discussed separately. The only one of these that shouldn't be classified as a failure is negotiation by compression, but even it shouldn't be taken as a role model considering its verbosity for basically negotiating one bit of information.

This page explains what’s wrong with each of the existing negotiation axes and then uses the HTML <code>video</code> element as an example for illustrating why HTTP-based negotiation in general is worse than letting the browser choose from alternative URLs by showing how an HTTP-based codec negotiation solution would be worse than the actual browser-side codec negotiation solution that <code>video</code> element uses.

==Negotiation by compression==

In practice, in the years HTTP has existed, a wide variety of compression methods has not cropped up. For practical purposes, there are two compression modes: uncompressed and gzipped. Google experimented with Shared Dictionary Compression over HTTP, but in practice it went nowhere on the wider Web. Even the Google-designed HTTP replacement SPDY uses gzip.

These days, all major browsers support gzipped responses. In that sense, the feature is a success. However, it is terribly wasteful that each request ends up containing 23 bytes of boilerplate. It would have been much more efficient if HTTP 1.1 had made the ability to accept gzipped responses a mandatory feature so that servers would have known that they are eligible to send a gzipped response if the request says HTTP/1.1 (or higher) rather than HTTP/1.0.

One might argue that it was important for getting from the HTTP/1.0 world to the world we have now by allowing new features to be opted into one by one and that format and protocol versions are an anti-pattern on the Web. In any case, it’s sad for the 1 bit of information to take 23 bytes—especially if HTTP is to have version number anyway and some features tied to the version number (like support for chunked responses).

==Negotiation by character encoding==

UTF-8 was introduced in 1993. By the time <code>Accept-Charset</code> was introduced, it was already obsolete in the sense that any server capable of converting to multiple encoding could have used its conversion capabilities to just convert to UTF-8. (Granted, UTF-8 support in browsers didn’t appear right away, but supporting UTF-8 sooner would have been more worthwhile than sending <code>Accept-Charset</code>.) Fortunately, we have been able to get rid of this one. Of the major browsers, only Chrome sends <code>Accept-Charset</code> anymore.

==Negotiation by natural language==

Negotiation by natural language is a failure for multiple reasons.

First, Web sites that provide content (as opposed to application user interface) in multiple languages so that the different language versions are so equally good that one language version could be selected without human judgment is actually very, very rare. When sites do have multiple language versions, the versions often are not equal. Typically, one language is the primary language for the site and the other language versions are incomplete, out of date or otherwise of low quality. Therefore, if the user can read more than one of the languages offered by the site, the user is most often best off choosing the language version to read manually by making a judgment about which language version that the user is able to read is most likely to be of highest quality. The negotiation algorithm tries to make this automatic, but in practice the algorithm is no substitute for the users human judgment.

It is slightly more common for Web applications to provide their UI strings in multiple languages. In that case, automatic choice might have a chance of working, but the user has a larger time commitment to a particular application anyway, so it is more okay for an application to provide an explicit language is UI than for a content site to require the user choose a language (which, per the previous paragraph, multilanguage content sites need to do anyway) making automatic negotiation less necessary for an application. Even though the initial value for the language preference for a Web application UI could be taken from what the browser suggests, the user starts using a new Web application so rarely relative to all HTTP requests that the user's browser makes that it is terribly wasteful for each HTTP request to broadcast the user's preferred language in case the request happens to be one whose headers and up seeding the preferences for a Web application. (And Web applications these days use JavaScript anyway and, therefore, could request the data from the browser instead of the browser broadcasting it with every HTTP request.)

Also, it's a problem that negotiation by natural language is about negotiating by a characteristic of the human user as opposed to a characteristic of software. That is, the browser doesn't really know the characteristics of the human user without the human user configuring the browser. Since negotiation by natural language is so rarely useful, it doesn't really make sense for the browser to advertise the configuration option a lot or insist that the user makes the configuration before browsing the Web. As a result, the browser doesn't really know about the user's language skills beyond guessing that the user might be able to read the UI language of the browser. And that's a pretty bad guess. It doesn't give any information about the other languages the user is able to read and the user might not even be able to actually read meaningful prose in the language of the browser UI. (You can get pretty far with the browser UI simply by knowing that you can type addresses into the location bar and that the arrow to the left takes you back to the previous page.)

Finally, there is an actual disincentive for configuring the browser: Even if everyone configured with their language preferences in their browser, the combination of languages that the person can read would partition the population of the world into rather small buckets in some cases making the language combination the way to identify a particular user or a smallish group of users. Since people so rarely configure their language preference, when someone does configure it, chances are that the configuration becomes uniquely or almost uniquely identifying. This can be seen as a privacy problem.

==Negotiating by format==

Negotiating by format is a failure because:

* It is actually rather rare that format alternatives can be chosen without knowing the user's intent. You might be able to choose automatically between different ways of compressing bitmaps, but choosing among e.g. a PDF and a Microsoft Word file might depend on the user's intent to print without reflowing lines due to different fonts on the system (PDF) or editing (Word) even if the user has software for reading both PDF and Microsoft Word files. Therefore, it makes sense to provide links to both the PDF and the Microsoft Word file and let the user choose which link to follow.

* You can’t rely on format negotiation as Web author, because there are always clients that accept something they don’t declare.

* Due to the previous point, if you are a browser vendor and another vendor has shipped a browser that doesn’t declare that it support something it supports, it doesn't make sense for you to waste bytes declaring it, either, because Web authors can’t rely (solely) on the declaration anyway.

* Negotiated responses are so rare relative to all HTTP responses that the request bloat resulting from advertising the supported formats is almost always waste.

* Past experience from the GIF to PNG transition suggests that authors are more likely to deploy one format—either the old one (with worse capabilities) or the new one (forgoing support for old browsers)—than actually bother using negotiation (as a generalization on the Web scale; there may be individual counterexamples that round to practical nothingness).

* It never pays to advertise a format once all current browsers support it but there are still old browsers that don't. (E.g. SVG as of 2013.) Since there are browsers that support the format that don't advertise it, the earlier point about not being able to rely on the declaration applies. However, since non-support is a past phenomenon, it is safe to UA sniff for the legacy browsers. If all current browsers support the format, there probably cannot be successful future browsers that don't support the format so the usual problem with you a sniffing where you assume that the current defect stays present in the future versions of a given browser does not apply.

==Server-side choice is worse for intermediate caches than browser-side choice==

Aside from script-driven HTTP requests (XHR), the HTTP requests made by browsers fall into two main categories: requests that arise from navigation
(HTML most of the time) and requests that arise from resource
inclusions (images, videos, audio, style sheets, fonts and scripts).

For resource inclusions, the server has always already sent
(unless the site uses SPDY push) an HTML document to the browser and
then the browser makes the requests in response to what it sees in
that document. That is, the server has had an opportunity to say something
to the browser already.

It is more friendly for intermediate caches for the resource (typically HTML document) that the server has alread sent to the browser to list alternative URLs for a resource inclusion request with information that allows the browser to choose which one of the URLs to fetch than to give the browser one URL and have the server vary what gets served from that URL.

Consider the actual design of the video element versus a hypothetical HTTP-based negotiation design
like this: There are no <code>source</code> elements. There is just the <code>src</code>
attribute on the <code>video</code> element. When making the request for the URL
given in the <code>src</code> attribute, the browser sends an <code>Accept-Codecs</code> HTTP
header that declares the supported container and codec combinations.
The server decides which video file to respond with depending on the
request header. The server sets the <code>Vary: Accept-Codecs</code> header on the response.

Now, intermediate caches have to use the value of the <code>Accept-Codecs</code>
header as part of the cache key.

Suppose the origin server has
two alternative video files MP4/H.264/AAC and WebM/VP8/Vorbis.
Ideally, this should result in at most two distinct cache entries and two cache keys in
an intermede cache. However, in this scenario, the worst case number for
the cache keys in the intermediary is the number of distinct
<code>Accept-Codec</code> values sent by the browsers out there.

Suppose first a browser that declares support for WebM/VP8/Vorbis request the video URL. The intermediate cache has no data for that URL yet, so it forwards the request to the origin server and caches the result with the URL and the value of the <code>Accept-Codecs</code> header as the cache key. Then another browser that declares support for MP4/H.264/AAC fetches the same URL from the same intermediate cache. The value of the <code>Accept-Codecs</code> header does not match the value in the existing cache key, so the intermediary cannot just go and serve the existing cache entry. Instead, it forwards the request to the origin server, gets a different response and makes new cache entry for that response with the URL and the different <code>Accept-Codecs</code> header value as the cache key. So now the intermediary has in its cache all the distinct video files that the origin server has for this URL. If the solution was properly cache-friendly, all subsequent requests could be served straight from the cache without consulting with the origin server until the entries' time to live expires.

But server-side negotiation isn't cache-friendly in that way. Suppose that now a browser that declares support for WebM/VP8/Vorbis ''and'' WebM/VP8/Opus makes a request for the same URL. The value of the <code>Accept-Codecs</code> header matches neither of the cache keys, so the intermediary needs to consult with the origin server even though it has cached all the possible variants already and one of them would be acceptable to this browser.

With the actual design of the video element, this problem does not occur. Each alternative video
file has a distinct URL, there is no need for the origin server to set
the Vary header and the result is as cache-friendly as possible. That
is, the worst case number of distinct cache keys is the number of
distinct videos on the origin server, so after the intermediary has cached them all, there is no need to consult with the origin server until the cache entries expire due to their age.

This example illustrates that solving the problem of choosing
between alternative resources on the HTTP level ends up being
less cache-friendly than letting the browser choose from
distinct URLs offered in the referring document.

[[Category:Justifications]]

MicrosyntaxDescriptions

2013-03-20T15:43:50Z

Hsivonen: Switch from the IANA registry to the Encoding Standard

The purpose of this page is to enable collaborative creation of brief advisory text for each HTML5 microsyntax so that when the content of an attribute value or the text content of an element does not conform to a given microsyntax, a validator can display the advisory text about the syntax to guide the author to fix the content. Note that like the rest of this wiki, editing requires you to agree to release your contributions under the MIT license (see wiki footer). Please note that while copying text from the [http://www.whatwg.org/specs/web-apps/current-work/ WHATWG version of HTML 5] is OK, copying text from RFCs or W3C specs is not OK.

Note that some formats pertain to Web Forms 2.0 (e.g. <code>datetime-local</code>).

Please keep descriptions short: one paragraph in length.

==a-rel==
A whitespace-separated list of link types, with no duplicate keywords in the list. Each link type must be listed as allowed on <code><a></code> and <code><area></code> in the [http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#linkTypes HTML specification], or must be listed as allowed on <code><a></code> and <code><area></code> on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki], or must be an absolute URL. You can register link types on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki] yourself.

==browsing-context==
A browsing context name is any string that does not start with an underscore (<code>_</code>).

==browsing-context-or-keyword==
A browsing context name or keyword is either any string that does not start with an underscore (<code>_</code>) or a string that case-insensitively matches one of: <code>_blank</code>, <code>_self</code>, <code>_parent</code>, or <code>_top</code>.

==cdo-cdc-pair==
Any text content that does not contain the character sequence "<code></code>".

==charset==
An preferred encoding name according to the [http://encoding.spec.whatwg.org/ Encoding Standard]. Example: <code>utf-8</code>

==charset-list==
A whitespace-separated list of preferred encoding names according to the [http://encoding.spec.whatwg.org/ Encoding Standard]. Example: <code>utf-8 windows-1252</code>

==circle==
A circle is specified as three comma-separated (no spaces allowed) integers the last one of which is non-negative. An integer consists of one or more digits (<code>0</code>–<code>9</code>), optionally preceded by a hyphen (<code>-</code>). Examples of circles: <code>5,5,10</code> and <code>-5,0,20</code>

==date==
A date in the form <code>YYYY-MM-DD</code>. Example: <code>2002-09-29</code>.

==date-or-time==
A [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-date-or-time-string date or time string]; that is, one of the following:
a date, which must be in the form <code>YYYY-MM-DD</code> • or, a time, which must begin in the form <code>hh:mm</code>, and can optionally be followed by <code>:ss</code>, which in turn can optionally be followed by “<code>.</code>” and one or more digits • or, a date, followed by “<code>T</code>”, followed by a time, followed by time-zone information, which must be either “<code>Z</code>”, or in the form <code>+hh:mm</code> or the form <code>-hh:mm</code> • Examples: <code>1996-01-01</code>, <code>12:05:25</code>, <code>1996-01-01T12:05:25-02:00</code>, <code>1996-01-01T12:05:25.6</code> • Note: The validator currently allows some values that the HTML specification prohibits; for example, it allows <code>1996-01-01T12:05:25</code> (a date and time with no time-zone information) and <code>12:05:25Z</code> (a time with no date but with time-zone information).

==datetime==
An ISO 8601 date and time in the UTC time zone, i.e. <code>YYYY-MM-DDThh:mm</code> optionally followed by <code>:ss</code> for the seconds, optionally followed by <code>.</code> and one, two, or three digits for the fraction of a second, and finally followed by <code>Z</code>. Examples: <code>1996-01-01T12:05Z</code>, <code>1996-01-01T12:05:25.6Z</code>.

==datetime-local==
An ISO 8601 date and time with no time zone information, i.e. <code>YYYY-MM-DDThh:mm</code> optionally followed by <code>:ss</code> for the seconds, optionally followed by <code>.</code> and one or more digits for the fraction of a second. Examples: <code>1996-01-01T12:05</code>, <code>1996-01-01T12:05:25.6</code>.

==datetime-tz==
A [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-global-date-and-time-string global date and time string]; that is, a date, followed by a “<code>T</code>” or a single space, followed by a time, followed by time-zone information, where: the date must be in the form <code>YYYY-MM-DD</code> • the time must begin in the form <code>hh:mm</code>, followed by <code>:ss</code>, optionally followed by “<code>.</code>” and one, two, or three or digits • the time-zone information must be either “<code>Z</code>” or in the form <code>+hh:mm</code> or the form <code>-hh:mm</code> • Examples: <code>1996-01-01T12:05:25-02:00</code>, <code>1996-01-01T12:05:25Z</code>



==email==
An e-mail address must match the <code>addr-spec</code> production defined in [http://tools.ietf.org/html/rfc2822#section-3.4.1 RFC 2822 section 3.4.1] excluding the <code>CFWS</code> production everywhere and excluding the <code>FWS</code> production everywhere except in the <code>quoted-string</code> production.

==float==
First, optionally, <code>-</code> (U+002D). Then, a series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, a single <code>.</code> (U+002E) followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. For example, <code>-42.42E+42</code> is valid but <code>.5</code> or <code>+2</code> are not.

==float-non-negative==
A series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, a single <code>.</code> (U+002E) followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. Or, alternatively to the foregoing: First, <code>-</code> (U+002D). Then, a series of one or more zeros. Then, optionally, a single <code>.</code> (U+002E) followed by one or more zeros. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. For example, <code>42.42E+42</code> and <code>-000.000</code> are valid but <code>.5</code> or <code>-0.01</code> are not.

==float-positive==
A series of one or more characters in the range <code>0</code>…<code>9</code>. Then, optionally, a single <code>.</code> (U+002E) followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. One of the digits so far has to be non-zero. Then, optionally, either <code>e</code> or <code>E</code>, optionally followed by <code>-</code> (U+002D) or <code>+</code> (U+002B), followed by a series of one or more characters in the range <code>0</code>…<code>9</code>. For example, <code>42.42E+42</code> is valid but <code>0.0</code> or <code>-2</code> are not.

==hash-name==
A <code>#</code> (number sign) character followed by any string.

==ID==
An ID consists of at least one character but must not contain any whitespace.

==integer==
One or more digits (<code>0</code>–<code>9</code>), optionally preceded by a hyphen (<code>-</code>). For example: <code>42</code> and <code>-273</code> are valid, but <code>+42</code> is not.

==integer-non-negative==
One or more digits (<code>0</code>–<code>9</code>). For example: <code>42</code> and <code>0</code> are valid, but <code>-273</code> is not.

==integer-positive==
One or more digits (<code>0</code>–<code>9</code>), with at least one which is non-zero. For example: <code>42</code> is valid, but <code>00</code> is not.

==iri==
An absolute URL. For example: <code><nowiki>http://</nowiki>example.org/hello</code>, but not <code>/hello</code>. Spaces should be escaped as <code>%20</code>.

==iri-ref==
Any URL. For example: <code>/hello</code>, <code>#canvas</code>, or <code><nowiki>http://</nowiki>example.org/</code>. Characters should be represented in [http://www.macchiato.com/unicode/nfc-faq NFC] and spaces should be escaped as <code>%20</code>.

==language==
An [http://tools.ietf.org/html/rfc5646 RFC 5646] language tag consists of hyphen-separated ASCII-alphanumeric subtags. There is a primary tag identifying a natural language by its shortest ISO 639 language code (e.g. <code>en</code> for English) and zero or more additional subtags adding precision. The most common additional subtag type is a region subtag which most commonly is a two-letter ISO 3166 country code (e.g. <code>GB</code> for the United Kingdom). IANA maintains a [http://www.iana.org/assignments/language-subtag-registry registry of permissible subtags].

==link-rel==
A whitespace-separated list of link types listed as allowed on <code><link></code> in the [http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#linkTypes HTML specification] or listed as an allowed on <code><link></code> on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki] without duplicate keywords in the list. You can register link types on the [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions Microformats wiki] yourself.

==media-query==
One or more media queries, combined in a comma-separated list. Each media query consists of a '''media type''' and zero or more expressions that check for the conditions of particular '''media features'''. A media type is one of the following: '''all''', '''braille''', '''embossed''', '''handheld''', '''print''', '''projection''', '''screen''', '''speech''', '''tty''', or '''tv'''. ''Note: The '''aural''' media type is deprecated''. For information about valid media features and about the exact syntax of media queries, see the [http://dev.w3.org/csswg/css3-mediaqueries/ Media Queries] specification.

==meta-charset==
The string <code>text/html;</code>, optionally followed by whitespace, followed by <code>charset=</code>, followed by a preferred encoding name according to the [http://encoding.spec.whatwg.org/ Encoding Standard]. Example: <code>text/html; charset=utf-8</code>

==meta-name==
A metadata name listed in the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#standard-metadata-names HTML specification] or listed in the [http://wiki.whatwg.org/wiki/MetaExtensions WHATWG wiki]. You can register metadata names on the [http://wiki.whatwg.org/wiki/MetaExtensions WHATWG wiki] yourself.

==mime-type==
A [http://tools.ietf.org/html/rfc2616#section-3.7 media-type as defined in RFC 2616]; that is, typically, a required ''type'', followed by a "<code>/</code>" character, followed by a required ''subtype'', optionally followed by one or more instances of a "<code>;</code>" character followed by a ''parameter''. Examples: <code>text/css</code>, <code>text/css;charset=utf-8</code>.

==mime-type-list==
(WF2)

==month==
An ISO 8601 date with year and month, i.e. <code>YYYY-MM</code>. Example: <code>2007-11</code>.

==non-empty-string==
Any string that is not the empty string.

==pattern==
(WF2)

==polyline==
...

==ratio==
(progress content)

==rectangle==
...

==script==
Any text content that does not contain the character sequence "<code></code>" and that does not contain any occurrence of the string "<code></script</code>" followed by a space character, "<code>></code>", or "<code>/</code>". For further details, see [http://www.whatwg.org/specs/web-apps/current-work/multipage/scripting-1.html#restrictions-for-contents-of-script-elements Restrictions for contents of script elements].

==script-documentation==
Zero or more ''code comments'', each of which is either a single-line comment starting with "<code>//</code>" or a multi-line comment starting with "<code>/*</code>" and ending with "<code>*/</code>". The content must also meet the constraints of the [[#script|script]] microsyntax. For further details, see [http://www.whatwg.org/specs/web-apps/current-work/multipage/scripting-1.html#inline-documentation-for-external-scripts Inline documentation for external scripts].

==simple-color==
A string of seven characters that starts with <code>#</code> and ends with six characters each of which is <code>0</code>…<code>9</code>, <code>a</code>…<code>f</code> or <code>A</code>…<code>F</code>.

==string-without-line-breaks==
Any string that does not contain the carriage return character or the line feed character.

==svg-pathdata==
A list of zero or more path-data expressions, where each expression consists of a one-letter command followed by numbers that serve as arguments for the command (in most cases, pairs of coordinates). Commas and/or whitespace must be used to separate the arguments for a command from one another—but '''commas must not be used to separate commands''', though whitespace can optionally be used to do so. Examples: "<code>M 100 100 L 300 100 L 200 300 z</code>" or "<code>M100,100L300,100,200,300z</code>". For more information, see the [http://www.w3.org/TR/SVG11/paths.html#PathData section on path data in the SVG 1.1 specification].

==time==
A time (hour, minute, seconds, fractional seconds) is encoded according to ISO 8601 with no time zone: two digits (<code>0</code>–<code>9</code>) for the hour, a colon, two digits for the minute, optionally a colon and two digits for the second, and optionally (if the seconds are present) a period (<code>.</code>) and one, two, or three digits for the fraction of a second. All the numbers must be in base ten and zero-padded if necessary. For instance: <code>23:59:00.000</code> or <code>00:00:05</code>.

==time-datetime==
One of the following: [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-month-string month], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-date-string date], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-yearless-date-string yearless date], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-time-string time], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-local-date-and-time-string local date and time], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-time-zone-offset-string time-zone offset], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-global-date-and-time-string global date and time], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-week-string week], [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-non-negative-integer non-negative integer], or [http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#valid-duration-string duration]. For more information and examples, see the [http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#datetime-value section on the datetime value in the HTML specification].

==week==
A week consists of a year and a week number encoded according to ISO 8601: four or more digits (<code>0</code>–<code>9</code>) representing the year, a hyphen (<code>-</code>), a literal <code>W</code>, and two digits for the week, zero-padded if necessary. The week number must be a number greater than or equal to <code>01</code>. Week <code>01</code> of a given year is the week containing the 4th of January; weeks start on Monday. For instance: <code>2005-W52</code> is the week that ended on Sunday the first of January, 2006.

[[Category:Validator.nu Documentation]]

Parser tests

2013-02-04T16:17:46Z

Hsivonen: Old svn URLS need to go away

=Parser Tests=

This page documents the unit-test format(s) being used for implementations of the HTML5 parsing spec. The aim is to produce implementation-independent, self-describing tests that can be shared between any groups working on these technologies.

==Tokenizer Tests==
The test format is [http://www.json.org/ JSON]. This has the advantage that the syntax allows backward-compatible extensions to the tests and the disadvantage that it is relatively verbose.

===Basic Structure===

{"tests": [

{"description":"Test description",
"input":"input_string",
"output":[expected_output_tokens]},
"contentModelFlags":[content_model_flags],
"lastStartTag":last_start_tag,
"ignoreErrorOrder":ignore_error_order
]}

<tt>description</tt>, <tt>input</tt> and <tt>output</tt> are always present. The other values are optional.

<tt>input_string</tt> is a string literal containing the input string to pass to the tokenizer.

<tt>expected_output_tokens</tt> is a list of tokens, ordered with the first produced by the tokenizer the first (leftmost) in the list. The list must mach the '''complete''' list of tokens that the tokenizer should produce. Valid tokens are:

["DOCTYPE", name, public_id, system_id, correctness]
["StartTag", name, {attributes}'', true'']
["StartTag", name, {attributes}]
["EndTag", name]
["Comment", data]
["Character", data]
"ParseError"

<tt>public_id</tt> and <tt>system_id</tt> are either strings or <tt>null</tt>. <tt>correctness</tt> is either <tt>true</tt> or <tt>false</tt>; <tt>true</tt> corresponds to the force-quirks flag being false, and vice-versa.

When the self-closing flag is set, the <tt>StartTag</tt> array has <tt>true</tt> as its fourth entry. When the flag is not set, the array has only three entries for backwards compatibility.

<tt>content_model_flags</tt> is a list of strings from the set:
PCDATA
RCDATA
RAWTEXT
PLAINTEXT
The test case applies when the tokenizer begins with its content model flag set to any of those values. If <tt>content_model_flags</tt> is omitted, it defaults to <tt>["PCDATA"]</tt>.

<tt>last_start_tag</tt> is a lowercase string that should be used as "the tag name of the last start tag token emitted" in the tokenizer algorithm. If it is omitted, it is treated as if "no start tag token has ever been emitted by this instance of the tokeniser".

<tt>ignore_error_order</tt> is a boolean value indicating that the order of <tt>ParseError</tt> tokens relative to other tokens in the output stream is unimportant, and implementations should ignore such differences between their output and <tt>expected_output_tokens</tt>. (This is used for errors emitted by the input stream preprocessing stage, since it is useful to test that code but it is undefined when the errors occur). If it is omitted, it defaults to <tt>false</tt>.

Multiple tests per file are allowed simply by adding more objects to the "tests" list.

All adjacent character tokens are coalesced into a single <tt>["Character", data]</tt> token.

=== Open Issues ===
* Is the format too verbose?
* Do we want to allow the test to pass if only a subset of the actual tokens emitted matches the expected_output_tokens list?

==Tree Construction Tests==

Each file containing tree construction tests consists of any number of tests separated by two newlines (LF) and a single newline before the end of the file. For instance:

<pre>[TEST]LF
LF
[TEST]LF
LF
[TEST]LF</pre>

Where [TEST] is the following format:

Each test must begin with a string "#data" followed by a newline (LF). All subsequent lines until a line that says "#errors" are the test data and must be passed to the system being tested unchanged, except with the final newline (on the last line) removed.

Then there must be a line that says "#errors". It must be followed by one line per parse error that a conformant checker would return. It doesn't matter what those lines are, although they can't be "#document-fragment", "#document", or empty, the only thing that matters is that there be the right number of parse errors.

Then there *may* be a line that says "#document-fragment", which must be followed by a newline (LF), followed by a string of characters that indicates the context element, followed by a newline (LF). If this line is present the "#data" must be parsed using the HTML fragment parsing algorithm with the context element as context.

Then there must be a line that says "#document", which must be followed by a dump of the tree of the parsed DOM. Each node must be represented by a single line. Each line must start with "| ", followed by two spaces per parent node that the node has before the root document node.
* Element nodes must be represented by a "<tt><</tt>" then the ''tag name string'' "<tt>></tt>", and all the attributes must be given, sorted lexicographically by UTF-16 code unit according to their ''attribute name string'', on subsequent lines, as if they were children of the element node.
* Attribute nodes must have the ''attribute name string'', then an "=" sign, then the attribute value in double quotes (").
* Text nodes must be the string, in double quotes. Newlines aren't escaped.
* Comments must be "<tt><</tt>" then "<tt>!-- </tt>" then the data then "<tt> --></tt>".
* DOCTYPEs must be "<tt><!DOCTYPE </tt>" then the name then if either of the system id or public id is non-empty a space, public id in double-quotes, another space an the system id in double-quotes, and then in any case "<tt>></tt>".
* Processing instructions must be "<tt><?</tt>", then the target, then a space, then the data and then "<tt>></tt>". (The HTML parser cannot emit processing instructions, but scripts can, and the WebVTT to DOM rules can emit them.)

The ''tag name string'' is the local name prefixed by a namespace designator. For the HTML namespace, the namespace designator is the empty string, i.e. there's no prefix. For the SVG namespace, the namespace designator is "svg ". For the MathML namespace, the namespace designator is "math ".

The ''attribute name string'' is the local name prefixed by a namespace designator. For no namespace, the namespace designator is the empty string, i.e. there's no prefix. For the XLink namespace, the namespace designator is "xlink ". For the XML namespace, the namespace designator is "xml ". For the XMLNS namespace, the namespace designator is "xmlns ". Note the difference between "xlink:href" which is an attribute in no namespace with the local name "xlink:href" and "xlink href" which is an attribute in the xlink namespace with the local name "href".

If there is also a "#document-fragment" the bit following "#document" must be a representation of the HTML fragment serialization for the context element given by "#document-fragment".

For example:
<pre>
#data
OneTwo
#errors
3: Missing document type declaration
#document
| <html>
| <head>
| <body>
| 
| "One"
| 
| "Two"
</pre>

Tests can be found here: http://code.google.com/p/html5lib/source/browse/#hg%2Ftestdata%2Ftree-construction

=== Open Issues ===
* should relax the order constraint?

Why not conneg

2013-01-30T08:39:55Z

Hsivonen: Emphasis wiki syntax, for real. Plus a clarification

The purpose of this page is to explain what's wrong with HTTP content negotiation and why you should not suggest HTTP content negotiation as a solution to a problem.

HTTP content negotiation has four axes: negotiation by format (<code>Accept</code>), negotiation by character encoding <code>Accept-Charset</code>, negotiation by natural language (<code>Accept-Language</code>) and negotiation by compression (<code>Accept-Encoding</code>). These axes need to be discussed separately. The only one of these that shouldn't be classified as a failure is negotiation by compression, but even it shouldn't be taken as a role model considering its verbosity for basically negotiating one bit of information.

This page explains what’s wrong with each of the existing negotiation axes and then uses the HTML <code>video</code> element as an example for illustrating why HTTP-based negotiation in general is worse than letting the browser choose from alternative URLs by showing how an HTTP-based codec negotiation solution would be worse than the actual browser-side codec negotiation solution that <code>video</code> element uses.

==Negotiation by compression==

In practice, in the years HTTP has existed, a wide variety of compression methods has not cropped up. For practical purposes, there are two compression modes: uncompressed and gzipped. Google experimented with Shared Dictionary Compression over HTTP, but in practice it went nowhere on the wider Web. Even the Google-designed HTTP replacement SPDY uses gzip.

These days, all major browsers support gzipped responses. In that sense, the feature is a success. However, it is terribly wasteful that each request ends up containing 23 bytes of boilerplate. It would have been much more efficient if HTTP 1.1 had made the ability to accept gzipped responses a mandatory feature so that servers would have known that they are eligible to send a gzipped response if the request says HTTP/1.1 (or higher) rather than HTTP/1.0.

One might argue that it was important for getting from the HTTP/1.0 world to the world we have now by allowing new features to be opted into one by one and that format and protocol versions are an anti-pattern on the Web. In any case, it’s sad for the 1 bit of information to take 23 bytes—especially if HTTP is to have version number anyway and some features tied to the version number (like support for chunked responses).

==Negotiation by character encoding==

UTF-8 was introduced in 1993. By the time <code>Accept-Charset</code> was introduced, it was already obsolete in the sense that any server capable of converting to multiple encoding could have used its conversion capabilities to just convert to UTF-8. (Granted, UTF-8 support in browsers didn’t appear right away, but supporting UTF-8 sooner would have been more worthwhile than sending <code>Accept-Charset</code>.) Fortunately, we have been able to get rid of this one. Of the major browsers, only Chrome sends <code>Accept-Charset</code> anymore.

==Negotiation by natural language==

Negotiation by natural language is a failure for multiple reasons.

First, Web sites that provide content (as opposed to application user interface) in multiple languages so that the different language versions are so equally good that one language version could be selected without human judgment is actually very, very rare. When sites do have multiple language versions, the versions often are not equal. Typically, one language is the primary language for the site and the other language versions are incomplete, out of date or otherwise of low quality. Therefore, if the user can read more than one of the languages offered by the site, the user is most often best off choosing the language version to read manually by making a judgment about which language version that the user is able to read is most likely to be of highest quality. The negotiation algorithm tries to make this automatic, but in practice the algorithm is no substitute for the users human judgment.

It is slightly more common for Web applications to provide their UI strings in multiple languages. In that case, automatic choice might have a chance of working, but the user has a larger time commitment to a particular application anyway, so it is more okay for an application to provide an explicit language is UI than for a content site to require the user choose a language (which, per the previous paragraph, multilanguage content sites need to do anyway) making automatic negotiation less necessary for an application. Even though the initial value for the language preference for a Web application UI could be taken from what the browser suggests, the user starts using a new Web application so rarely relative to all HTTP requests that the user's browser makes that it is terribly wasteful for each HTTP request to broadcast the user's preferred language in case the request happens to be one whose headers and up seeding the preferences for a Web application. (And Web applications these days use JavaScript anyway and, therefore, could request the data from the browser instead of the browser broadcasting it with every HTTP request.)

Also, it's a problem that negotiation by natural language is about negotiating by a characteristic of the human user as opposed to a characteristic of software. That is, the browser doesn't really know the characteristics of the human user without the human user configuring the browser. Since negotiation by natural language is so rarely useful, it doesn't really make sense for the browser to advertise the configuration option a lot or insist that the user makes the configuration before browsing the Web. As a result, the browser doesn't really know about the user's language skills beyond guessing that the user might be able to read the UI language of the browser. And that's a pretty bad guess. It doesn't give any information about the other languages the user is able to read and the user might not even be able to actually read meaningful prose in the language of the browser UI. (You can get pretty far with the browser UI simply by knowing that you can type addresses into the location bar and that the arrow to the left takes you back to the previous page.)

Finally, there is an actual disincentive for configuring the browser: Even if everyone configured with their language preferences in their browser, the combination of languages that the person can read would partition the population of the world into rather small buckets in some cases making the language combination the way to identify a particular user or a smallish group of users. Since people so rarely configure their language preference, when someone does configure it, chances are that the configuration becomes uniquely or almost uniquely identifying. This can be seen as a privacy problem.

==Negotiating by format==

Negotiating by format is a failure because:

* It is actually rather rare that format alternatives can be chosen without knowing the user's intent. You might be able to choose automatically between different ways of compressing bitmaps, but choosing among e.g. a PDF and a Microsoft Word file might depend on the user's intent to print without reflowing lines due to different fonts on the system (PDF) or editing (Word) even if the user has software for reading both PDF and Microsoft Word files. Therefore, it makes sense to provide links to both the PDF and the Microsoft Word file and let the user choose which link to follow.

* You can’t rely on format negotiation as Web author, because there are always clients that accept something they don’t declare.

* Due to the previous point, if you are a browser vendor and another vendor has shipped a browser that doesn’t declare that it support something it supports, it doesn't make sense for you to waste bytes declaring it, either, because Web authors can rely (solely) on the declaration anyway.

* Negotiated responses are so rare relative to all HTTP responses that the request bloat resulting from advertising the supported formats is almost always waste.

* Past experience from the GIF to PNG transition suggests that authors are more likely to deploy one format either the old one (with worse capabilities) or the new one (forgoing support for old browsers) than actually bother using negotiation (as a generalization on the Web scale; there may be individual counterexamples that round to practical nothingness).

* It never pays to advertise a format once all current browsers support it but there are still old browsers that don't. (E.g. SVG as of 2013.) Since there are browsers that support the format that don't advertise it, the earlier point about not being able to rely on the declaration applies. However, since non-support is a past phenomenon, it is safe to UA sniff for the legacy browsers. If all current browsers support the format, there probably cannot be successful future browsers that don't support the format so the usual problem with you a sniffing where you assume that the current defect stays present in the future versions of a given browser does not apply.

==Server-side choice is worse for intermediate caches than browser-side choice==

Aside from script-driven HTTP requests (XHR), the HTTP requests made by browsers fall into two main categories: requests that arise from navigation
(HTML most of the time) and requests that arise from resource
inclusions (images, videos, audio, style sheets, fonts and scripts).

For resource inclusions, the server has always already sent
(unless the site uses SPDY push) an HTML document to the browser and
then the browser makes the requests in response to what it sees in
that document. That is, the server has had an opportunity to say something
to the browser already.

It is more friendly for intermediate caches for the resource (typically HTML document) that the server has alread sent to the browser to list alternative URLs for a resource inclusion request with information that allows the browser to choose which one of the URLs to fetch than to give the browser one URL and have the server vary what gets served from that URL.

Consider the actual design of the video element versus a hypothetical HTTP-based negotiation design
like this: There are no <code>source</code> elements. There is just the <code>src</code>
attribute on the <code>video</code> element. When making the request for the URL
given in the <code>src</code> attribute, the browser sends an <code>Accept-Codecs</code> HTTP
header that declares the supported container and codec combinations.
The server decides which video file to respond with depending on the
request header. The server sets the <code>Vary: Accept-Codecs</code> header on the response.

Now, intermediate caches have to use the value of the <code>Accept-Codecs</code>
header as part of the cache key.

Suppose the origin server has
two alternative video files MP4/H.264/AAC and WebM/VP8/Vorbis.
Ideally, this should result in at most two distinct cache entries and two cache keys in
an intermede cache. However, in this scenario, the worst case number for
the cache keys in the intermediary is the number of distinct
<code>Accept-Codec</code> values sent by the browsers out there.

Suppose first a browser that declares support for WebM/VP8/Vorbis request the video URL. The intermediate cache has no data for that URL yet, so it forwards the request to the origin server and caches the result with the URL and the value of the <code>Accept-Codecs</code> header as the cache key. Then another browser that declares support for MP4/H.264/AAC fetches the same URL from the same intermediate cache. The value of the <code>Accept-Codecs</code> header does not match the value in the existing cache key, so the intermediary cannot just go and serve the existing cache entry. Instead, it forwards the request to the origin server, gets a different response and makes new cache entry for that response with the URL and the different <code>Accept-Codecs</code> header value as the cache key. So now the intermediary has in its cache all the distinct video files that the origin server has for this URL. If the solution was properly cache-friendly, all subsequent requests could be served straight from the cache without consulting with the origin server until the entries' time to live expires.

But server-side negotiation isn't cache-friendly in that way. Suppose that now a browser that declares support for WebM/VP8/Vorbis ''and'' WebM/VP8/Opus makes a request for the same URL. The value of the <code>Accept-Codecs</code> header matches neither of the cache keys, so the intermediary needs to consult with the origin server even though it has cached all the possible variants already and one of them would be acceptable to this browser.

With the actual design of the video element, this problem does not occur. Each alternative video
file has a distinct URL, there is no need for the origin server to set
the Vary header and the result is as cache-friendly as possible. That
is, the worst case number of distinct cache keys is the number of
distinct videos on the origin server, so after the intermediary has cached them all, there is no need to consult with the origin server until the cache entries expire due to their age.

This example illustrates that solving the problem of choosing
between alternative resources on the HTTP level ends up being
less cache-friendly than letting the browser choose from
distinct URLs offered in the referring document.

Why not conneg

2013-01-30T08:37:53Z

Hsivonen: Emphasis wiki syntax

The purpose of this page is to explain what's wrong with HTTP content negotiation and why you should not suggest HTTP content negotiation as a solution to a problem.

HTTP content negotiation has four axes: negotiation by format (<code>Accept</code>), negotiation by character encoding <code>Accept-Charset</code>, negotiation by natural language (<code>Accept-Language</code>) and negotiation by compression (<code>Accept-Encoding</code>). These axes need to be discussed separately. The only one of these that shouldn't be classified as a failure is negotiation by compression, but even it shouldn't be taken as a role model considering its verbosity for basically negotiating one bit of information.

This page explains what’s wrong with each of the existing negotiation axes and then uses the HTML <code>video</code> element as an example for illustrating why HTTP-based negotiation in general is worse than letting the browser choose from alternative URLs by showing how an HTTP-based codec negotiation solution would be worse than the actual browser-side codec negotiation solution that <code>video</code> element uses.

==Negotiation by compression==

In practice, in the years HTTP has existed, a wide variety of compression methods has not cropped up. For practical purposes, there are two compression modes: uncompressed and gzipped. Google experimented with Shared Dictionary Compression over HTTP, but in practice it went nowhere on the wider Web. Even the Google-designed HTTP replacement SPDY uses gzip.

These days, all major browsers support gzipped responses. In that sense, the feature is a success. However, it is terribly wasteful that each request ends up containing 23 bytes of boilerplate. It would have been much more efficient if HTTP 1.1 had made the ability to accept gzipped responses a mandatory feature so that servers would have known that they are eligible to send a gzipped response if the request says HTTP/1.1 (or higher) rather than HTTP/1.0.

One might argue that it was important for getting from the HTTP/1.0 world to the world we have now by allowing new features to be opted into one by one and that format and protocol versions are an anti-pattern on the Web. In any case, it’s sad for the 1 bit of information to take 23 bytes—especially if HTTP is to have version number anyway and some features tied to the version number (like support for chunked responses).

==Negotiation by character encoding==

UTF-8 was introduced in 1993. By the time <code>Accept-Charset</code> was introduced, it was already obsolete in the sense that any server capable of converting to multiple encoding could have used its conversion capabilities to just convert to UTF-8. (Granted, UTF-8 support in browsers didn’t appear right away, but supporting UTF-8 sooner would have been more worthwhile than sending <code>Accept-Charset</code>.) Fortunately, we have been able to get rid of this one. Of the major browsers, only Chrome sends <code>Accept-Charset</code> anymore.

==Negotiation by natural language==

Negotiation by natural language is a failure for multiple reasons.

First, Web sites that provide content (as opposed to application user interface) in multiple languages so that the different language versions are so equally good that one language version could be selected without human judgment is actually very, very rare. When sites do have multiple language versions, the versions often are not equal. Typically, one language is the primary language for the site and the other language versions are incomplete, out of date or otherwise of low quality. Therefore, if the user can read more than one of the languages offered by the site, the user is most often best off choosing the language version to read manually by making a judgment about which language version that the user is able to read is most likely to be of highest quality. The negotiation algorithm tries to make this automatic, but in practice the algorithm is no substitute for the users human judgment.

It is slightly more common for Web applications to provide their UI strings in multiple languages. In that case, automatic choice might have a chance of working, but the user has a larger time commitment to a particular application anyway, so it is more okay for an application to provide an explicit language is UI than for a content site to require the user choose a language (which, per the previous paragraph, multilanguage content sites need to do anyway) making automatic negotiation less necessary for an application. Even though the initial value for the language preference for a Web application UI could be taken from what the browser suggests, the user starts using a new Web application so rarely relative to all HTTP requests that the user's browser makes that it is terribly wasteful for each HTTP request to broadcast the user's preferred language in case the request happens to be one whose headers and up seeding the preferences for a Web application. (And Web applications these days use JavaScript anyway and, therefore, could request the data from the browser instead of the browser broadcasting it with every HTTP request.)

Also, it's a problem that negotiation by natural language is about negotiating by a characteristic of the human user as opposed to a characteristic of software. That is, the browser doesn't really know the characteristics of the human user without the human user configuring the browser. Since negotiation by natural language is so rarely useful, it doesn't really make sense for the browser to advertise the configuration option a lot or insist that the user makes the configuration before browsing the Web. As a result, the browser doesn't really know about the user's language skills beyond guessing that the user might be able to read the UI language of the browser. And that's a pretty bad guess. It doesn't give any information about the other languages the user is able to read and the user might not even be able to actually read meaningful prose in the language of the browser UI. (You can get pretty far with the browser UI simply by knowing that you can type addresses into the location bar and that the arrow to the left takes you back to the previous page.)

Finally, there is an actual disincentive for configuring the browser: Even if everyone configured with their language preferences in their browser, the combination of languages that the person can read would partition the population of the world into rather small buckets in some cases making the language combination the way to identify a particular user or a smallish group of users. Since people so rarely configure their language preference, when someone does configure it, chances are that the configuration becomes uniquely or almost uniquely identifying. This can be seen as a privacy problem.

==Negotiating by format==

Negotiating by format is a failure because:

* It is actually rather rare that format alternatives can be chosen without knowing the user's intent. You might be able to choose automatically between different ways of compressing bitmaps, but choosing among e.g. a PDF and a Microsoft Word file might depend on the user's intent to print without reflowing lines due to different fonts on the system (PDF) or editing (Word) even if the user has software for reading both PDF and Microsoft Word files. Therefore, it makes sense to provide links to both the PDF and the Microsoft Word file and let the user choose which link to follow.

* You can’t rely on format negotiation as Web author, because there are always clients that accept something they don’t declare.

* Due to the previous point, if you are a browser vendor and another vendor has shipped a browser that doesn’t declare that it support something it supports, it doesn't make sense for you to waste bytes declaring it, either, because Web authors can rely (solely) on the declaration anyway.

* Negotiated responses are so rare relative to all HTTP responses that the request bloat resulting from advertising the supported formats is almost always waste.

* Past experience from the GIF to PNG transition suggests that authors are more likely to deploy one format either the old one (with worse capabilities) or the new one (forgoing support for old browsers) than actually bother using negotiation (as a generalization on the Web scale; there may be individual counterexamples that round to practical nothingness).

* It never pays to advertise a format once all current browsers support it but there are still old browsers that don't. (E.g. SVG as of 2013.) Since there are browsers that support the format that don't advertise it, the earlier point about not being able to rely on the declaration applies. However, since non-support is a past phenomenon, it is safe to UA sniff for the legacy browsers. If all current browsers support the format, there probably cannot be successful future browsers that don't support the format so the usual problem with you a sniffing where you assume that the current defect stays present in the future versions of a given browser does not apply.

==Server-side choice is worse for intermediate caches than browser-side choice==

Aside from script-driven HTTP requests (XHR), the HTTP requests made by browsers fall into two main categories: requests that arise from navigation
(HTML most of the time) and requests that arise from resource
inclusions (images, videos, audio, style sheets, fonts and scripts).

For resource inclusions, the server has always already sent
(unless the site uses SPDY push) an HTML document to the browser and
then the browser makes the requests in response to what it sees in
that document. That is, the server has had an opportunity to say something
to the browser already.

It is more friendly for intermediate caches for the resource (typically HTML document) that the server has alread sent to the browser to list alternative URLs for a resource inclusion request with information that allows the browser to choose which one of the URLs to fetch than to give the browser one URL and have the server vary what gets served from that URL.

Consider the actual design of the video element versus a hypothetical HTTP-based negotiation design
like this: There are no <code>source</code> elements. There is just the <code>src</code>
attribute on the <code>video</code> element. When making the request for the URL
given in the <code>src</code> attribute, the browser sends an <code>Accept-Codecs</code> HTTP
header that declares the supported container and codec combinations.
The server decides which video file to respond with depending on the
request header. The server sets the <code>Vary: Accept-Codecs</code> header on the response.

Now, intermediate caches have to use the value of the <code>Accept-Codecs</code>
header as part of the cache key.

Suppose the origin server has
two alternative video files MP4/H.264/AAC and WebM/VP8/Vorbis.
Ideally, this should result in at most two distinct cache entries and two cache keys in
an intermede cache. However, in this scenario, the worst case number for
the cache keys in the intermediary is the number of distinct
<code>Accept-Codec</code> values sent by the browsers out there.

Suppose first a browser that declares support for WebM/VP8/Vorbis request the video URL. The intermediate cache has no data for that URL yet, so it forwards the request to the origin server and caches the result with the URL and the value of the <code>Accept-Codecs</code> header as the cache key. Then another browser that declares support for MP4/H.264/AAC fetches the same URL from the same intermediate cache. The value of the <code>Accept-Codecs</code> header does not match the value in the existing cache key, so the intermediary cannot just go and serve the existing cache entry. Instead, it forwards the request to the origin server, gets a different response and makes new cache entry for that response with the URL and the different <code>Accept-Codecs</code> header value as the cache key. So now the intermediary has in its cache all the distinct video files that the origin server has for this URL. If the solution was properly cache-friendly, all subsequent requests could be served straight from the cache without consulting with the origin server until the entries' time to live expires.

But server-side negotiation isn't cache-friendly in that way. Suppose that now a browser that declares support for WebM/VP8/Vorbis _and_ WebM/VP8/Opus makes a request for the same URL. The value of the <code>Accept-Codecs</code> header matches neither of the cache keys, so the intermediary needs to consult with the origin server even though it has cached all the possible variants already.

With the actual design of the video element, this problem does not occur. Each alternative video
file has a distinct URL, there is no need for the origin server to set
the Vary header and the result is as cache-friendly as possible. That
is, the worst case number of distinct cache keys is the number of
distinct videos on the origin server, so after the intermediary has cached them all, there is no need to consult with the origin server until the cache entries expire due to their age.

This example illustrates that solving the problem of choosing
between alternative resources on the HTTP level ends up being
less cache-friendly than letting the browser choose from
distinct URLs offered in the referring document.

Why not conneg

2013-01-30T08:35:40Z

Hsivonen: Mention codec example in intro

The purpose of this page is to explain what's wrong with HTTP content negotiation and why you should not suggest HTTP content negotiation as a solution to a problem.

HTTP content negotiation has four axes: negotiation by format (<code>Accept</code>), negotiation by character encoding <code>Accept-Charset</code>, negotiation by natural language (<code>Accept-Language</code>) and negotiation by compression (<code>Accept-Encoding</code>). These axes need to be discussed separately. The only one of these that shouldn't be classified as a failure is negotiation by compression, but even it shouldn't be taken as a role model considering its verbosity for basically negotiating one bit of information.

This page explains what’s wrong with each of the existing negotiation axes and then uses the HTML <code>video</code> element as an example for illustrating why HTTP-based negotiation in general is worse than letting the browser choose from alternative URLs by showing how an HTTP-based codec negotiation solution would be worse than the actual browser-side codec negotiation solution that <code>video</code> element uses.

==Negotiation by compression==

In practice, in the years HTTP has existed, a wide variety of compression methods has not cropped up. For practical purposes, there are two compression modes: uncompressed and gzipped. Google experimented with Shared Dictionary Compression over HTTP, but in practice it went nowhere on the wider Web. Even the Google-designed HTTP replacement SPDY uses gzip.

These days, all major browsers support gzipped responses. In that sense, the feature is a success. However, it is terribly wasteful that each request ends up containing 23 bytes of boilerplate. It would have been much more efficient if HTTP 1.1 had made the ability to accept gzipped responses a mandatory feature so that servers would have known that they are eligible to send a gzipped response if the request says HTTP/1.1 (or higher) rather than HTTP/1.0.

One might argue that it was important for getting from the HTTP/1.0 world to the world we have now by allowing new features to be opted into one by one and that format and protocol versions are an anti-pattern on the Web. In any case, it’s sad for the 1 bit of information to take 23 bytes—especially if HTTP is to have version number anyway and some features tied to the version number (like support for chunked responses).

==Negotiation by character encoding==

UTF-8 was introduced in 1993. By the time <code>Accept-Charset</code> was introduced, it was already obsolete in the sense that any server capable of converting to multiple encoding could have used its conversion capabilities to just convert to UTF-8. (Granted, UTF-8 support in browsers didn’t appear right away, but supporting UTF-8 sooner would have been more worthwhile than sending <code>Accept-Charset</code>.) Fortunately, we have been able to get rid of this one. Of the major browsers, only Chrome sends <code>Accept-Charset</code> anymore.

==Negotiation by natural language==

Negotiation by natural language is a failure for multiple reasons.

First, Web sites that provide content (as opposed to application user interface) in multiple languages so that the different language versions are so equally good that one language version could be selected without human judgment is actually very, very rare. When sites do have multiple language versions, the versions often are not equal. Typically, one language is the primary language for the site and the other language versions are incomplete, out of date or otherwise of low quality. Therefore, if the user can read more than one of the languages offered by the site, the user is most often best off choosing the language version to read manually by making a judgment about which language version that the user is able to read is most likely to be of highest quality. The negotiation algorithm tries to make this automatic, but in practice the algorithm is no substitute for the users human judgment.

It is slightly more common for Web applications to provide their UI strings in multiple languages. In that case, automatic choice might have a chance of working, but the user has a larger time commitment to a particular application anyway, so it is more okay for an application to provide an explicit language is UI than for a content site to require the user choose a language (which, per the previous paragraph, multilanguage content sites need to do anyway) making automatic negotiation less necessary for an application. Even though the initial value for the language preference for a Web application UI could be taken from what the browser suggests, the user starts using a new Web application so rarely relative to all HTTP requests that the user's browser makes that it is terribly wasteful for each HTTP request to broadcast the user's preferred language in case the request happens to be one whose headers and up seeding the preferences for a Web application. (And Web applications these days use JavaScript anyway and, therefore, could request the data from the browser instead of the browser broadcasting it with every HTTP request.)

Also, it's a problem that negotiation by natural language is about negotiating by a characteristic of the human user as opposed to a characteristic of software. That is, the browser doesn't really know the characteristics of the human user without the human user configuring the browser. Since negotiation by natural language is so rarely useful, it doesn't really make sense for the browser to advertise the configuration option a lot or insist that the user makes the configuration before browsing the Web. As a result, the browser doesn't really know about the user's language skills beyond guessing that the user might be able to read the UI language of the browser. And that's a pretty bad guess. It doesn't give any information about the other languages the user is able to read and the user might not even be able to actually read meaningful prose in the language of the browser UI. (You can get pretty far with the browser UI simply by knowing that you can type addresses into the location bar and that the arrow to the left takes you back to the previous page.)

Finally, there is an actual disincentive for configuring the browser: Even if everyone configured with their language preferences in their browser, the combination of languages that the person can read would partition the population of the world into rather small buckets in some cases making the language combination the way to identify a particular user or a smallish group of users. Since people so rarely configure their language preference, when someone does configure it, chances are that the configuration becomes uniquely or almost uniquely identifying. This can be seen as a privacy problem.

==Negotiating by format==

Negotiating by format is a failure because:

* It is actually rather rare that format alternatives can be chosen without knowing the user's intent. You might be able to choose automatically between different ways of compressing bitmaps, but choosing among e.g. a PDF and a Microsoft Word file might depend on the user's intent to print without reflowing lines due to different fonts on the system (PDF) or editing (Word) even if the user has software for reading both PDF and Microsoft Word files. Therefore, it makes sense to provide links to both the PDF and the Microsoft Word file and let the user choose which link to follow.

* You can’t rely on format negotiation as Web author, because there are always clients that accept something they don’t declare.

* Due to the previous point, if you are a browser vendor and another vendor has shipped a browser that doesn’t declare that it support something it supports, it doesn't make sense for you to waste bytes declaring it, either, because Web authors can rely (solely) on the declaration anyway.

* Negotiated responses are so rare relative to all HTTP responses that the request bloat resulting from advertising the supported formats is almost always waste.

* Past experience from the GIF to PNG transition suggests that authors are more likely to deploy one format either the old one (with worse capabilities) or the new one (forgoing support for old browsers) than actually bother using negotiation (as a generalization on the Web scale; there may be individual counterexamples that round to practical nothingness).

* It never pays to advertise a format once all current browsers support it but there are still old browsers that don't. (E.g. SVG as of 2013.) Since there are browsers that support the format that don't advertise it, the earlier point about not being able to rely on the declaration applies. However, since non-support is a past phenomenon, it is safe to UA sniff for the legacy browsers. If all current browsers support the format, there probably cannot be successful future browsers that don't support the format so the usual problem with you a sniffing where you assume that the current defect stays present in the future versions of a given browser does not apply.

==Server-side choice is worse for intermediate caches than browser-side choice==

Aside from script-driven HTTP requests (XHR), the HTTP requests made by browsers fall into two main categories: requests that arise from navigation
(HTML most of the time) and requests that arise from resource
inclusions (images, videos, audio, style sheets, fonts and scripts).

For resource inclusions, the server has always already sent
(unless the site uses SPDY push) an HTML document to the browser and
then the browser makes the requests in response to what it sees in
that document. That is, the server has had an opportunity to say something
to the browser already.

It is more friendly for intermediate caches for the resource (typically HTML document) that the server has alread sent to the browser to list alternative URLs for a resource inclusion request with information that allows the browser to choose which one of the URLs to fetch than to give the browser one URL and have the server vary what gets served from that URL.

Consider the actual design of the video element versus a hypothetical HTTP-based negotiation design
like this: There are no <code>source</code> elements. There is just the <code>src</code>
attribute on the <code>video</code> element. When making the request for the URL
given in the <code>src</code> attribute, the browser sends an <code>Accept-Codecs</code> HTTP
header that declares the supported container and codec combinations.
The server decides which video file to respond with depending on the
request header. The server sets the <code>Vary: Accept-Codecs</code> header on the response.

Now, intermediate caches have to use the value of the <code>Accept-Codecs</code>
header as part of the cache key.

Suppose the origin server has
two alternative video files MP4/H.264/AAC and WebM/VP8/Vorbis.
Ideally, this should result in at most two distinct cache entries and two cache keys in
an intermede cache. However, in this scenario, the worst case number for
the cache keys in the intermediary is the number of distinct
<code>Accept-Codec</code> values sent by the browsers out there.

Suppose first a browser that declares support for WebM/VP8/Vorbis request the video URL. The intermediate cache has no data for that URL yet, so it forwards the request to the origin server and caches the result with the URL and the value of the <code>Accept-Codecs</code> header as the cache key. Then another browser that declares support for MP4/H.264/AAC fetches the same URL from the same intermediate cache. The value of the <code>Accept-Codecs</code> header does not match the value in the existing cache key, so the intermediary cannot just go and serve the existing cache entry. Instead, it forwards the request to the origin server, gets a different response and makes new cache entry for that response with the URL and the different <code>Accept-Codecs</code> header value as the cache key. So now the intermediary has in its cache all the distinct video files that the origin server has for this URL. If the solution was properly cache-friendly, all subsequent requests could be served straight from the cache without consulting with the origin server until the entries' time to live expires.

But server-side negotiation isn't cache-friendly in that way. Suppose that now a browser that declares support for WebM/VP8/Vorbis *and* WebM/VP8/Opus makes a request for the same URL. The value of the <code>Accept-Codecs</code> header matches neither of the cache keys, so the intermediary needs to consult with the origin server even though it has cached all the possible variants already.

With the actual design of the video element, this problem does not occur. Each alternative video
file has a distinct URL, there is no need for the origin server to set
the Vary header and the result is as cache-friendly as possible. That
is, the worst case number of distinct cache keys is the number of
distinct videos on the origin server, so after the intermediary has cached them all, there is no need to consult with the origin server until the cache entries expire due to their age.

This example illustrates that solving the problem of choosing
between alternative resources on the HTTP level ends up being
less cache-friendly than letting the browser choose from
distinct URLs offered in the referring document.

Why not conneg

2013-01-30T08:32:38Z

Hsivonen: Explain why all conneg in less cache-friendly than letting the browser choose

The purpose of this page is to explain what's wrong with HTTP content negotiation and why you should not suggest HTTP content negotiation as a solution to a problem.

HTTP content negotiation has four axes: negotiation by format (<code>Accept</code>), negotiation by character encoding <code>Accept-Charset</code>, negotiation by natural language (<code>Accept-Language</code>) and negotiation by compression (<code>Accept-Encoding</code>). These axes need to be discussed separately. The only one of these that shouldn't be classified as a failure is negotiation by compression, but even it shouldn't be taken as a role model considering its verbosity for basically negotiating one bit of information.

==Negotiation by compression==

In practice, in the years HTTP has existed, a wide variety of compression methods has not cropped up. For practical purposes, there are two compression modes: uncompressed and gzipped. Google experimented with Shared Dictionary Compression over HTTP, but in practice it went nowhere on the wider Web. Even the Google-designed HTTP replacement SPDY uses gzip.

These days, all major browsers support gzipped responses. In that sense, the feature is a success. However, it is terribly wasteful that each request ends up containing 23 bytes of boilerplate. It would have been much more efficient if HTTP 1.1 had made the ability to accept gzipped responses a mandatory feature so that servers would have known that they are eligible to send a gzipped response if the request says HTTP/1.1 (or higher) rather than HTTP/1.0.

One might argue that it was important for getting from the HTTP/1.0 world to the world we have now by allowing new features to be opted into one by one and that format and protocol versions are an anti-pattern on the Web. In any case, it’s sad for the 1 bit of information to take 23 bytes—especially if HTTP is to have version number anyway and some features tied to the version number (like support for chunked responses).

==Negotiation by character encoding==

UTF-8 was introduced in 1993. By the time <code>Accept-Charset</code> was introduced, it was already obsolete in the sense that any server capable of converting to multiple encoding could have used its conversion capabilities to just convert to UTF-8. (Granted, UTF-8 support in browsers didn’t appear right away, but supporting UTF-8 sooner would have been more worthwhile than sending <code>Accept-Charset</code>.) Fortunately, we have been able to get rid of this one. Of the major browsers, only Chrome sends <code>Accept-Charset</code> anymore.

==Negotiation by natural language==

Negotiation by natural language is a failure for multiple reasons.

First, Web sites that provide content (as opposed to application user interface) in multiple languages so that the different language versions are so equally good that one language version could be selected without human judgment is actually very, very rare. When sites do have multiple language versions, the versions often are not equal. Typically, one language is the primary language for the site and the other language versions are incomplete, out of date or otherwise of low quality. Therefore, if the user can read more than one of the languages offered by the site, the user is most often best off choosing the language version to read manually by making a judgment about which language version that the user is able to read is most likely to be of highest quality. The negotiation algorithm tries to make this automatic, but in practice the algorithm is no substitute for the users human judgment.

It is slightly more common for Web applications to provide their UI strings in multiple languages. In that case, automatic choice might have a chance of working, but the user has a larger time commitment to a particular application anyway, so it is more okay for an application to provide an explicit language is UI than for a content site to require the user choose a language (which, per the previous paragraph, multilanguage content sites need to do anyway) making automatic negotiation less necessary for an application. Even though the initial value for the language preference for a Web application UI could be taken from what the browser suggests, the user starts using a new Web application so rarely relative to all HTTP requests that the user's browser makes that it is terribly wasteful for each HTTP request to broadcast the user's preferred language in case the request happens to be one whose headers and up seeding the preferences for a Web application. (And Web applications these days use JavaScript anyway and, therefore, could request the data from the browser instead of the browser broadcasting it with every HTTP request.)

Also, it's a problem that negotiation by natural language is about negotiating by a characteristic of the human user as opposed to a characteristic of software. That is, the browser doesn't really know the characteristics of the human user without the human user configuring the browser. Since negotiation by natural language is so rarely useful, it doesn't really make sense for the browser to advertise the configuration option a lot or insist that the user makes the configuration before browsing the Web. As a result, the browser doesn't really know about the user's language skills beyond guessing that the user might be able to read the UI language of the browser. And that's a pretty bad guess. It doesn't give any information about the other languages the user is able to read and the user might not even be able to actually read meaningful prose in the language of the browser UI. (You can get pretty far with the browser UI simply by knowing that you can type addresses into the location bar and that the arrow to the left takes you back to the previous page.)

Finally, there is an actual disincentive for configuring the browser: Even if everyone configured with their language preferences in their browser, the combination of languages that the person can read would partition the population of the world into rather small buckets in some cases making the language combination the way to identify a particular user or a smallish group of users. Since people so rarely configure their language preference, when someone does configure it, chances are that the configuration becomes uniquely or almost uniquely identifying. This can be seen as a privacy problem.

==Negotiating by format==

Negotiating by format is a failure because:

* It is actually rather rare that format alternatives can be chosen without knowing the user's intent. You might be able to choose automatically between different ways of compressing bitmaps, but choosing among e.g. a PDF and a Microsoft Word file might depend on the user's intent to print without reflowing lines due to different fonts on the system (PDF) or editing (Word) even if the user has software for reading both PDF and Microsoft Word files. Therefore, it makes sense to provide links to both the PDF and the Microsoft Word file and let the user choose which link to follow.

* You can’t rely on format negotiation as Web author, because there are always clients that accept something they don’t declare.

* Due to the previous point, if you are a browser vendor and another vendor has shipped a browser that doesn’t declare that it support something it supports, it doesn't make sense for you to waste bytes declaring it, either, because Web authors can rely (solely) on the declaration anyway.

* Negotiated responses are so rare relative to all HTTP responses that the request bloat resulting from advertising the supported formats is almost always waste.

* Past experience from the GIF to PNG transition suggests that authors are more likely to deploy one format either the old one (with worse capabilities) or the new one (forgoing support for old browsers) than actually bother using negotiation (as a generalization on the Web scale; there may be individual counterexamples that round to practical nothingness).

* It never pays to advertise a format once all current browsers support it but there are still old browsers that don't. (E.g. SVG as of 2013.) Since there are browsers that support the format that don't advertise it, the earlier point about not being able to rely on the declaration applies. However, since non-support is a past phenomenon, it is safe to UA sniff for the legacy browsers. If all current browsers support the format, there probably cannot be successful future browsers that don't support the format so the usual problem with you a sniffing where you assume that the current defect stays present in the future versions of a given browser does not apply.

==Server-side choice is worse for intermediate caches than browser-side choice==

Aside from script-driven HTTP requests (XHR), the HTTP requests made by browsers fall into two main categories: requests that arise from navigation
(HTML most of the time) and requests that arise from resource
inclusions (images, videos, audio, style sheets, fonts and scripts).

For resource inclusions, the server has always already sent
(unless the site uses SPDY push) an HTML document to the browser and
then the browser makes the requests in response to what it sees in
that document. That is, the server has had an opportunity to say something
to the browser already.

It is more friendly for intermediate caches for the resource (typically HTML document) that the server has alread sent to the browser to list alternative URLs for a resource inclusion request with information that allows the browser to choose which one of the URLs to fetch than to give the browser one URL and have the server vary what gets served from that URL.

Consider the actual design of the video element versus a hypothetical HTTP-based negotiation design
like this: There are no <code>source</code> elements. There is just the <code>src</code>
attribute on the <code>video</code> element. When making the request for the URL
given in the <code>src</code> attribute, the browser sends an <code>Accept-Codecs</code> HTTP
header that declares the supported container and codec combinations.
The server decides which video file to respond with depending on the
request header. The server sets the <code>Vary: Accept-Codecs</code> header on the response.

Now, intermediate caches have to use the value of the <code>Accept-Codecs</code>
header as part of the cache key.

Suppose the origin server has
two alternative video files MP4/H.264/AAC and WebM/VP8/Vorbis.
Ideally, this should result in at most two distinct cache entries and two cache keys in
an intermede cache. However, in this scenario, the worst case number for
the cache keys in the intermediary is the number of distinct
<code>Accept-Codec</code> values sent by the browsers out there.

Suppose first a browser that declares support for WebM/VP8/Vorbis request the video URL. The intermediate cache has no data for that URL yet, so it forwards the request to the origin server and caches the result with the URL and the value of the <code>Accept-Codecs</code> header as the cache key. Then another browser that declares support for MP4/H.264/AAC fetches the same URL from the same intermediate cache. The value of the <code>Accept-Codecs</code> header does not match the value in the existing cache key, so the intermediary cannot just go and serve the existing cache entry. Instead, it forwards the request to the origin server, gets a different response and makes new cache entry for that response with the URL and the different <code>Accept-Codecs</code> header value as the cache key. So now the intermediary has in its cache all the distinct video files that the origin server has for this URL. If the solution was properly cache-friendly, all subsequent requests could be served straight from the cache without consulting with the origin server until the entries' time to live expires.

But server-side negotiation isn't cache-friendly in that way. Suppose that now a browser that declares support for WebM/VP8/Vorbis *and* WebM/VP8/Opus makes a request for the same URL. The value of the <code>Accept-Codecs</code> header matches neither of the cache keys, so the intermediary needs to consult with the origin server even though it has cached all the possible variants already.

With the actual design of the video element, this problem does not occur. Each alternative video
file has a distinct URL, there is no need for the origin server to set
the Vary header and the result is as cache-friendly as possible. That
is, the worst case number of distinct cache keys is the number of
distinct videos on the origin server, so after the intermediary has cached them all, there is no need to consult with the origin server until the cache entries expire due to their age.

This example illustrates that solving the problem of choosing
between alternative resources on the HTTP level ends up being
less cache-friendly than letting the browser choose from
distinct URLs offered in the referring document.

Band names

2013-01-29T13:24:19Z

Hsivonen: Ambiguous Ampersands

Why not conneg

2013-01-17T12:20:14Z

Hsivonen: Mention accept-charset, discuss HTTP versioning some more

Why not conneg

2013-01-08T09:53:29Z

Hsivonen: Grammar fix to remove stray articles

Why not conneg

2013-01-07T15:22:05Z

Hsivonen: /* Negotiation by natural language */ Minor word error fix

The purpose of this page is to explain what's wrong with a HTTP content negotiation and why you should not suggest a HTTP content negotiation as a solution to a problem.

HTTP content negotiation has three axes: negotiation by format (<code>Accept</code>), negotiation by natural language (<code>Accept-Language</code>) and negotiation by compression (<code>Accept-Encoding</code>). These axes need to be discussed separately. The only one of these that shouldn't be classified as a failure is negotiation by compression, but even it shouldn't be taken as a role model considering its verbosity for basically negotiating one bit of information.

==Negotiation by compression==

In practice, in the years HTTP has existed, a wide variety of compression methods has not cropped up. For practical purposes, there are two compression modes: uncompressed and gzipped. Google experimented with Shared Dictionary Compression over HTTP, but in practice it went nowhere on the wider Web. Even the Google-designed HTTP replacement SPDY uses gzip.

These days, all major browsers support gzipped responses. In that sense, the feature is a success. However, it is terribly wasteful that each request ends up containing 23 bytes of boilerplate. It would have been much more efficient if HTTP 1.1 had made the ability to accept gzipped responses a mandatory feature so that servers would have known that they are eligible to send a gzipped response if the request says HTTP/1.1 (or higher) rather than HTTP/1.0.

==Negotiation by natural language==

Negotiation by natural language is a failure for multiple reasons.

First, Web sites that provide content (as opposed to application user interface) in multiple languages so that the different language versions are so equally good that one language version could be selected without human judgment is actually very, very rare. When sites do have multiple language versions, the versions often are not equal. Typically, one language is the primary language for the site and the other language versions are incomplete, out of date or otherwise of low quality. Therefore, if the user can read more than one of the languages offered by the site, the user is most often best off choosing the language version to read manually by making a judgment about which language version that the user is able to read is most likely to be of highest quality. The negotiation algorithm tries to make this automatic, but in practice the algorithm is no substitute for the users human judgment.

It is slightly more common for Web applications to provide their UI strings in multiple languages. In that case, automatic choice might have a chance of working, but the user has a larger time commitment to a particular application anyway, so it is more okay for an application to provide an explicit language is UI than for a content site to require the user choose a language (which, per the previous paragraph, multilanguage content sites need to do anyway) making automatic negotiation less necessary for an application. Even though the initial value for the language preference for a Web application UI could be taken from what the browser suggests, the user starts using a new Web application so rarely relative to all HTTP requests that the user's browser makes that it is terribly wasteful for each HTTP request to broadcast the user's preferred language in case the request happens to be one whose headers and up seeding the preferences for a Web application. (And Web applications these days use JavaScript anyway and, therefore, could request the data from the browser instead of the browser broadcasting it with every HTTP request.)

Also, it's a problem that negotiation by natural language is about negotiating by a characteristic of the human user as opposed to a characteristic of software. That is, the browser doesn't really know the characteristics of the human user without the human user configuring the browser. Since negotiation by natural language is so rarely useful, it doesn't really make sense for the browser to advertise the configuration option a lot or insist that the user makes the configuration before browsing the Web. As a result, the browser doesn't really know about the user's language skills beyond guessing that the user might be able to read the UI language of the browser. And that's a pretty bad guess. It doesn't give any information about the other languages the user is able to read and the user might not even be able to actually read meaningful prose in the language of the browser UI. (You can get pretty far with the browser UI simply by knowing that you can type addresses into the location bar and that the arrow to the left takes you back to the previous page.)

Finally, there is an actual disincentive for configuring the browser: Even if everyone configured with their language preferences in their browser, the combination of languages that the person can read would partition the population of the world into rather small buckets in some cases making the language combination the way to identify a particular user or a smallish group of users. Since people so rarely configure their language preference, when someone does configure it, chances are that the configuration becomes uniquely or almost uniquely identifying. This can be seen as a privacy problem.

==Negotiating by format==

Negotiating by format is a failure because:

* It is actually rather rare that format alternatives can be chosen without knowing the user's intent. You might be able to choose automatically between different ways of compressing bitmaps, but choosing among e.g. a PDF and a Microsoft Word file might depend on the user's intent to print without reflowing lines due to different fonts on the system (PDF) or editing (Word) even if the user has software for reading both PDF and Microsoft Word files. Therefore, it makes sense to provide links to both the PDF and the Microsoft Word file and let the user choose which link to follow.

* You can’t rely on format negotiation as Web author, because there are always clients that accept something they don’t declare.

* Due to the previous point, if you are a browser vendor and another vendor has shipped a browser that doesn’t declare that it support something it supports, it doesn't make sense for you to waste bytes declaring it, either, because Web authors can rely (solely) on the declaration anyway.

* Negotiated responses are so rare relative to all HTTP responses that the request bloat resulting from advertising the supported formats is almost always waste.

* Past experience from the GIF to PNG transition suggests that authors are more likely to deploy one format either the old one (with worse capabilities) or the new one (forgoing support for old browsers) than actually bother using negotiation (as a generalization on the Web scale; there may be individual counterexamples that round to practical nothingness).

* It never pays to advertise a format once all current browsers support it but there are still old browsers that don't. (E.g. SVG as of 2013.) Since there are browsers that support the format that don't advertise it, the earlier point about not being able to rely on the declaration applies. However, since non-support is a past phenomenon, it is safe to UA sniff for the legacy browsers. If all current browsers support the format, there probably cannot be successful future browsers that don't support the format so the usual problem with you a sniffing where you assume that the current defect stays present in the future versions of a given browser does not apply.

Why not conneg

2013-01-07T15:04:17Z

Hsivonen: Add content

The purpose of this page is to explain what's wrong with a HTTP content negotiation and why you should not suggest a HTTP content negotiation as a solution to a problem.

HTTP content negotiation has three axes: negotiation by format (<code>Accept</code>), negotiation by natural language (<code>Accept-Language</code>) and negotiation by compression (<code>Accept-Encoding</code>). These axes need to be discussed separately. The only one of these that shouldn't be classified as a failure is negotiation by compression, but even it shouldn't be taken as a role model considering its verbosity for basically negotiating one bit of information.

==Negotiation by compression==

In practice, in the years HTTP has existed, a wide variety of compression methods has not cropped up. For practical purposes, there are two compression modes: uncompressed and gzipped. Google experimented with Shared Dictionary Compression over HTTP, but in practice it went nowhere on the wider Web. Even the Google-designed HTTP replacement SPDY uses gzip.

These days, all major browsers support gzipped responses. In that sense, the feature is a success. However, it is terribly wasteful that each request ends up containing 23 bytes of boilerplate. It would have been much more efficient if HTTP 1.1 had made the ability to accept gzipped responses a mandatory feature so that servers would have known that they are eligible to send a gzipped response if the request says HTTP/1.1 (or higher) rather than HTTP/1.0.

==Negotiation by natural language==

Negotiation by natural language is a failure for multiple reasons.

First, Web sites that provide content (as opposed to application user interface) in multiple languages so that the different language versions are so equally good that one language version could be selected without human judgment is actually very, very rare. When sites do have multiple language versions, the versions often are not equal. Typically, one language is the primary language for the site and the other language versions are incomplete, out of date or otherwise of low quality. Therefore, if the user can read more than one of the languages offered by the site, the user is most often best off choosing the language version to read manually by making a judgment about which language version that the user is able to read is most likely to be of highest quality. The negotiation algorithm tries to make this automatic, but in practice the algorithm is no substitute for the users human judgment.

It is slightly more common for Web applications to provide their UI strings in multiple languages. In that case, automatic choice might have a chance of working, but the user has a larger time commitment to a particular application anyway, so it is more okay for an application to provide an explicit language is UI than for a content site to require the user choose a language (which, per the previous paragraph, multilanguage content sites need to do anyway) making automatic negotiation less necessary for an application. Even though the initial value for the language preference for a Web application UI could be taken from what the browser suggests, the user starts using a new Web application so rarely relative to all HTTP requests that the user's browser makes that it is terribly wasteful for each HTTP request to broadcast the user's preferred language in case the request happens to be one whose headers and up seeding the preferences for a Web application. (And Web applications these days use JavaScript anyway and, therefore, could request the data from the browser instead of the browser broadcasting it with every HTTP request.)

Also, it's a problem that negotiation by natural language is about negotiating by a characteristic of the human user as opposed to a characteristic all software. That is, the browser doesn't really know the characteristics of the human user without the human user configuring the browser. Since negotiation by natural language is so rarely useful, it doesn't really make sense for the browser to advertise the configuration option a lot or insist that the user makes the configuration before browsing the Web. As a result, the browser doesn't really know about the user's language skills beyond guessing that the user might be able to read the UI language of the browser. And that's a pretty bad guess. It doesn't give any information about the other languages the user is able to read and the user might not even be able to actually read meaningful prose in the language of the browser UI. (You can get pretty far with the browser UI simply by knowing that you can type addresses into the location bar and that the arrow to the left takes you back to the previous page.)

Finally, there is an actual disincentive for configuring the browser: Even if everyone configured with their language preferences in their browser, the combination of languages that the person can read would partition the population of the world into rather small buckets in some cases making the language combination the way to identify a particular user or a smallish group of users. Since people so rarely configure their language preference, when someone does configure it, chances are that the configuration becomes uniquely or almost uniquely identifying. This can be seen as a privacy problem.

==Negotiating by format==

Negotiating by format is a failure because:

* It is actually rather rare that format alternatives can be chosen without knowing the user's intent. You might be able to choose automatically between different ways of compressing bitmaps, but choosing among e.g. a PDF and a Microsoft Word file might depend on the user's intent to print without reflowing lines due to different fonts on the system (PDF) or editing (Word) even if the user has software for reading both PDF and Microsoft Word files. Therefore, it makes sense to provide links to both the PDF and the Microsoft Word file and let the user choose which link to follow.

* You can’t rely on format negotiation as Web author, because there are always clients that accept something they don’t declare.

* Due to the previous point, if you are a browser vendor and another vendor has shipped a browser that doesn’t declare that it support something it supports, it doesn't make sense for you to waste bytes declaring it, either, because Web authors can rely (solely) on the declaration anyway.

* Negotiated responses are so rare relative to all HTTP responses that the request bloat resulting from advertising the supported formats is almost always waste.

* Past experience from the GIF to PNG transition suggests that authors are more likely to deploy one format either the old one (with worse capabilities) or the new one (forgoing support for old browsers) than actually bother using negotiation (as a generalization on the Web scale; there may be individual counterexamples that round to practical nothingness).

* It never pays to advertise a format once all current browsers support it but there are still old browsers that don't. (E.g. SVG as of 2013.) Since there are browsers that support the format that don't advertise it, the earlier point about not being able to rely on the declaration applies. However, since non-support is a past phenomenon, it is safe to UA sniff for the legacy browsers. If all current browsers support the format, there probably cannot be successful future browsers that don't support the format so the usual problem with you a sniffing where you assume that the current defect stays present in the future versions of a given browser does not apply.

Why not conneg

2013-01-07T14:06:45Z

Hsivonen: Created

The purpose of this page is to explain what's wrong with a HTTP content negotiation and why you should not suggest a HTTP content negotiation as a solution to a problem.

Band names

2012-10-19T13:38:50Z

Hsivonen: Added band names

These are band names collected from #whatwg.

* Bogus DOM
* The Unpaired Surrogates
* The Designated Experts
* Spidermonkey and the GC Jitters
* Polyglot Heartbeat

Bad Ideas

2012-06-05T07:25:03Z

Hsivonen: /* Browsers should accept byte code from the network instead of other languages having to be compiled into JS */ Expand on byte code problems

The purpose of this page is to collect explanations why commonly-proposed bad ideas for the Web are bad, so that they don't need to be explained over and over again.

==It should be possible to escape from CSS to a Turing-complete language like JS==

This would introduce at least one of these problems:

* Styling couldn't be applied incrementally if the styling program needs to run from start to finish with the entire document has its input. XSLT suffers from this problem.

* Content changes couldn't be efficiently reflected in layout by doing partial updates if the style system had to analyze a Turing-complete program to see if it affects the styling of a particular subtree.

* If the Turing-complete language allowed side effects, the style system couldn't decide when to re-resolve styles. Instead, style re-resolution times would have to be specified in the standard in order to get interoperable side effects.

* Even now, some oft-requested selectors aren't supported due to time-complexity issues. It would be hard to curb bad time-complexity if arbitrary programs were allowed to run as part of styling.

* The environment in which the Turing-complete language program with run would have to be specified and would constrain the implementation of the style system.

==Browsers should accept byte code from the network instead of other languages having to be compiled into JS==

* Java's byte code compat limited where the language could go. Needed a complex byte code verifier to make sure the low-level operations don't combine to something dangerous.

* JS is already supported, so compiling to JS enjoys better benefits from network effects that launching a new byte code.

* Using gzip compression on JS produces an already supported binary representation of JS.

* The language needs to be able to call some APIs in the environment. In the browser, those are DOM APIs which are single-threaded. In order to call those APIs, the new languages are limited by JS's concurrency model anyway. Otherwise, there's a need to reinvent the world on the API side as well. The JDK was a huge parallel system to the browser-native APIs. Pepper as available to NaCl reinvents a lot of APIs that have Web-native analogs.

* You can't standardize an existing JS VM byte code: SpiderMonkey and SquirrelFish both have byte code but they are of very different designs (stack-based vs. register-based) and neither is designed to be ingested from untrusted sources. V8 doesn't have a byte code.

* Adding a few features to JS that make it a better compilation target is a smaller step from the status quo than launching something completely new.

* A new byte code design wouldn't be unbiased towards a kind of language anyway. (See e.g. Java byte code and later additions to better support dynamic languages.) Might as well accept the biases of JS as the interchange format.

* There's a lot of JS out there, so browsers need to compete on JS performance anyway. Using JS as the interchange intermediate language helps leverage that work instead of involving parallel work for a parallel system.

* See [http://www.infoq.com/presentations/The-JavaScript-World-Domination-Plan-at-16-Years this talk by Brendan Eich] from 22:30 onwards. (Should transcribe the points here in due course.)

Bad Ideas

2012-06-04T14:34:18Z

Hsivonen: Wording, grammar, time complexity

Bad Ideas

2012-06-04T14:30:32Z

Hsivonen: Start a list of bad ideas

MetaExtensions

2011-12-19T08:44:45Z

Hsivonen: Move gm-gpx-v to incomplete proposals

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Incomplete proposal
| Claimed spec link is not a link to a spec

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Incomplete proposal
| Claimed spec link is not a link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Incomplete proposal
| The claimed spec doesn't actually specify meta keyword

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Incomplete proposal
| Claimed spec link does not link to a spec

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Incomplete proposal
| Claimed spec URL is not a spec URL

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-12-19T08:40:38Z

Hsivonen: Move the Open Graph Protocol stuff to incomplete proposals

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Incomplete proposal
| The spec specifies this to be a value of the property attribute--not a meta keyword

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Incomplete proposal
| Claimed spec link is not a link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Incomplete proposal
| The claimed spec doesn't actually specify meta keyword

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Incomplete proposal
| Claimed spec link does not link to a spec

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Incomplete proposal
| Claimed spec URL is not a spec URL

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-12-19T08:35:45Z

Hsivonen: Move nibbler-site-verification to incomplete proposals

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Incomplete proposal
| Claimed spec link is not a link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Incomplete proposal
| The claimed spec doesn't actually specify meta keyword

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Incomplete proposal
| Claimed spec link does not link to a spec

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Incomplete proposal
| Claimed spec URL is not a spec URL

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-12-19T08:33:37Z

Hsivonen: Move blogcatalog to incomplete proposals

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Proposal

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Incomplete proposal
| Claimed spec link is not a link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Incomplete proposal
| The claimed spec doesn't actually specify meta keyword

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Incomplete proposal
| Claimed spec URL is not a spec URL

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-12-19T08:31:20Z

Hsivonen: Move wot-verification to incomplete proposals

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Proposal

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Proposal

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Incomplete proposal
| The claimed spec doesn't actually specify meta keyword

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Incomplete proposal
| Claimed spec URL is not a spec URL

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-12-19T08:21:36Z

Hsivonen: Sort dc.language correctly

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Proposal

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Proposal

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Proposal

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Incomplete proposal
| The claimed spec doesn't actually specify meta keyword

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-12-19T08:19:56Z

Hsivonen: Move citeseerxbot to incomplete proposals

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Proposal

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Proposal

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Proposal

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Incomplete proposal
| The claimed spec doesn't actually specify meta keyword

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-12-19T08:14:28Z

Hsivonen: Move nextgen to bogus registration attempts

'''To create an account, please ask someone in the #whatwg [[IRC]] channel on Freenode, or e-mail ian@hixie.ch. We had to disable open signups because the level of spam became intolerable.'''

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| citeseerxbot
| Synonym of <code>robots</code> for targeting CiteSeerX only.
| [http://csxstatic.ist.psu.edu/about/crawler CiteSeerX Crawler documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dc.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dc.language</code>)
<code>dc.language</code> is preferred by several web validators over <code>dcterms.language</code>
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| designer
| Credits the designer(s) responsible for the visual presentation of a website.
| [https://sites.google.com/site/metadesignerspec/ Documenation]
|
| Proposal

|-valign="top"
| EssayDirectory
| Defines a custom description of websites listed in EssayDirectory. Example:
<meta name="EssayDirectory" content="Helping students find legitimate essay services.">
| [http://essaydirectory.com/privacy-terms/#EssayDirectory_MetaExtension Documenation]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.country
| Case-insensitive ISO 3166-1 alpha-2 code of a country to which the page is related to. Example:
<meta name="geo.country" content="de">
| [http://www.syndic8.com/help_metadata.php All About Feed Metadata]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| revisit-after
| revisit-after is used to tell search engines how often to recrawl the page. To our knowledge only one search engine has ever supported it, and that search engine was never widely used — at this point, it is nothing more than a good luck charm.
| [http://code.google.com/webstats/2005-12/metadata.html Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| HandheldFriendly
| Denotes handheld-friendly content
| [http://learnthemobileweb.com/tag/handheldfriendly/]
|
| Proposal

|-valign="top"
| MobileOptimized
| Denotes content optimized for mobile browsers
| [http://learnthemobileweb.com/tag/mobileoptimized/]
|
| Proposal

|-valign="top"
| itemsPerPage
| Used to identify the number of search results returned per page.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| startIndex
| Used to identify the index of the first search result in the current set of search results.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| totalResults
| Used to identify the number of search results available for the current search.
| [http://www.opensearch.org/Specifications/OpenSearch/1.1#Response_metadata_in_HTML.2FXHTML OpenSearch Specification]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| wot-verification
| Used to verify ownership of WOT (Web Of Trust)
| [http://www.mywot.com/ WOT site]
|
| Proposal

|-valign="top"
| blogcatalog
| Used to verify ownership of Blog Catalog.com
| [http://www.blogcatalog.com/ Blog catalog site]
|
| Proposal

|-valign="top"
| nibbler-site-verification
| Used to verify ownership of Nibbler site
| [http://nibbler.silktide.com/ Nibbler site]
|
| Proposal

|-valign="top"
| og:title
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:type
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:url
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:image
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:site_name
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:admins
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| og:description
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| fb:page_id
| Open Graph Protocol by Facebook developers
| [http://developers.facebook.com/docs/opengraph/ Facebook developers]
|
| Proposal

|-valign="top"
| gm-gpx-v
| Wordpress Plugin Google Maps GPX Viewer
| [http://wordpress.org/extend/plugins/google-maps-gpx-viewer/ Google Maps GPX Viewer]
|
| Proposal

|-valign="top"
| meta_date
| The date used to indicate that the Metadata has been prepared and/or reviewed and approved by the Metadata Unit. Its purpose is administrative. (Used by "Autonomy".)
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| nextgen
| Used for nextgen gallery plugin in wordpress
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Incomplete proposal
| Unrelated spec link

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

Validator.nu parser

2011-11-15T12:01:03Z

Hsivonen: Point to the hg repo

The [http://about.validator.nu/htmlparser/ Validator.nu HTML parser] is an implementation of the HTML5 parsing algorithm in Java with SAX, XOM and DOM interfaces.

The code is available from
<pre>hg clone https://hg.mozilla.org/projects/htmlparser/</pre>

More information from hsivonen at #whatwg.

[[Category:Implementations]]
[[Category:Validator.nu Documentation]]

MetaExtensions

2011-08-31T10:22:25Z

Hsivonen: Undo bogus edit removing some wiki syntax

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dcterms.abstract
| A summary of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-abstract DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accessRights
| Information about who can access the resource or an indication of its security status.
| [http://dublincore.org/documents/dcmi-terms/#terms-accessRights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualMethod
| The method by which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPeriodicity
| The frequency with which items are added to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPeriodicity DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.accrualPolicy
| The policy governing the addition of items to a collection.
| [http://dublincore.org/documents/dcmi-terms/#terms-accrualPolicy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.alternative
| An alternative name for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-alternative DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.audience
| A class of entity for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-audience DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.available
| Date (often a range) that the resource became or will become available.
| [http://dublincore.org/documents/dcmi-terms/#terms-available DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.bibliographicCitation
| A bibliographic reference for the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-bibliographicCitation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>cite</code>
| Proposal

|-valign="top"
| dcterms.conformsTo
| An established standard to which the described resource conforms.
| [http://dublincore.org/documents/dcmi-terms/#terms-conformsTo DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.contributor
| An entity responsible for making contributions to the content of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-contributor DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.coverage
| The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.
| [http://dublincore.org/documents/dcmi-terms/#terms-coverage DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.created
| Date of creation of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-created DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of
a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword
| <code>author</code> Proposal

|-valign="top"
| dcterms.date
| A point or period of time associated with an event in the lifecycle of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-date DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateAccepted
| Date of acceptance of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateAccepted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateCopyrighted
| Date of copyright.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateCopyrighted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.dateSubmitted
| Date of submission of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-dateSubmitted DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not
limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.educationLevel
| A class of entity, defined in terms of progression through an educational or training context, for which the described resource is intended.
| [http://dublincore.org/documents/dcmi-terms/#terms-educationLevel DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.extent
| The size or duration of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-extent DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.format
| The file format, physical medium, or dimensions of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-format DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasFormat
| A related resource that is substantially the same as the pre-existing described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasFormat DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.hasPart
| A related resource that is included either physically or logically in the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasPart DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.hasVersion
| A related resource that is a version, edition, or adaptation of the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-hasVersion DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.identifier
| An unambiguous reference to the resource within a given context.
| [http://dublincore.org/documents/dcmi-terms/#terms-identifier DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.instructionalMethod
| A process used to engender knowledge, attitudes and skills, that the described resource is designed to support.
| [http://dublincore.org/documents/dcmi-terms/#terms-instructionalMethod DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isFormatOf
| A related resource that is substantially the same as the described resource, but in another format.
| [http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.isPartOf
| A related resource in which the described resource is physically or logically included.
| [http://dublincore.org/documents/dcmi-terms/#terms-isPartOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReferencedBy
| A related resource that references, cites, or otherwise points to the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReferencedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isReplacedBy
| A related resource that supplants, displaces, or supersedes the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-isReplacedBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.isRequiredBy
| A related resource that requires the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-isRequiredBy DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC
doesn't spec a date format but the established practice is
YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.isVersionOf
| A related resource of which the described resource is a version, edition, or adaptation.
| [http://dublincore.org/documents/dcmi-terms/#terms-isVersionOf DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML link type keyword "alternate" used with "link" element:<code>rel="alternate" type="URI of related resource"</code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a
controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the
<code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.license
| A legal document giving official permission to do something with the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-license DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>license</code>
| Proposal

|-valign="top"
| dcterms.mediator
| An entity that mediates access to the resource and for whom the resource is intended or useful.
| [http://dublincore.org/documents/dcmi-terms/#terms-mediator DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.medium
| The material or physical carrier of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-medium DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date
format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.provenance
| A statement for any changes in ownership and custody of the resource since its creation that are significant for its authenticity, integrity, and interpretation.
| [http://dublincore.org/documents/dcmi-terms/#terms-provenance DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.publisher
| An entity responsible for making the resource available.
| [http://dublincore.org/documents/dcmi-terms/#terms-publisher DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.references
| A related resource that is referenced, cited, or otherwise pointed to by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-references DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.relation
| A related resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-relation DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.replaces
| A related resource that is supplanted, displaced, or superseded by the described resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-replaces DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.requires
| A related resource that is required by the described resource to support its function, delivery, or coherence.
| [http://dublincore.org/documents/dcmi-terms/#terms-requires DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rights
| Information about rights held in and over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rights DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.rightsHolder
| A person or organization owning or managing rights over the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-rightsHolder DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.source
| A related resource from which the described resource is derived.
| [http://dublincore.org/documents/dcmi-terms/#terms-source DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.spatial
| Spatial characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-spatial DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.tableOfContents
| A list of subunits of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-tableOfContents DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.temporal
| Temporal characteristics of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-temporal DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| dcterms.type
| The nature or genre of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-type DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.valid
| Date (often a range) of validity of a resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-valid DCMI
Metadata Terms] mapped according to
[http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
| defacto standard, used in nearly every website, e.g. [http://www.gaijin.at/olsmgen.php][http://developers.evrsoft.com/metagen.shtml][http://www.html-seminar.de/metatags.htm]
|
| Proposal

|-valign="top"
| review_date
| The date a resource is scheduled for review by content creator in order to determine if it should be archived, updated or retained as is.
| [http://www.hc-sc.gc.ca/home-accueil/alt_formats/pacrb-dgapcr/pdf/Metadata_Application_Profile_2009.pdf Health Canada Web Metadata Application Profile March 2009 ]
|
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-08-04T15:30:41Z

Hsivonen: Move og:* off the registry list

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword <code>author</code>
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the <code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Doesn't belong in this registry
| Not a value to be used in the <code>name</code> attribute

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-08-04T15:24:35Z

Hsivonen: Curate the ICBM entry: sort properly, add a more appropriate URL, add synonym

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword <code>author</code>
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the <code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
| icbm (different value syntax)
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| icbm
| Defines geographic position to which page is related to. The acronym stands for ICBM Intercontinental Ballistic Missile - an old, humorous allusion to the possible use of such coordinates. Example:
<meta name="ICBM" content="47.0667, 15.4500" />
| [http://geourl.org/add.html GeoURL documentation]
| geo.position (different value syntax)
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msapplication-starturl
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-starturl" metadata contains the root URL of the application. The start URL can be fully qualified, or relative to the current document. Only HTTP and HTTPS protocols are allowed. If this element is missing, the address of the current page is used instead.
<meta name="msapplication-starturl" content="./" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-tooltip
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-tooltip" metadata provides additional tooltip text that appears when you hover over the Pinned Site shortcut in the Windows Start menu or on the desktop.
<meta name="msapplication-tooltip" content="Channel 9 Podcasts" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msapplication-navbutton-color
| '''"Jump List" or "Pinned Sites" in Windows 7'''
The "msapplication-navbutton-color" metadata define the custom color of the Back and Forward buttons in the Pinned Site browser window. Any named color, or hex color value is valid.
<meta name="msapplication-navbutton-color" content="#FF3300" />
| [http://msdn.microsoft.com/en-us/library/gg491732(v=VS.85).aspx Declaring Pinned Site Metadata]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|-valign="top"
| property="og:*"
| Metadata used by the Open Graph protocol (used by Facebook). Note: currently these are defined as: <meta property="og.*" content="x"/>
| [http://developers.facebook.com/docs/opengraph/ FAQ About the Open Graph protocol from Facebook.]
|
| Proposal

|-valign="top"
| globrix.instruction
| Globrix property information: Property to Buy or Rent
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.price
| Globrix property information: Price for the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.postcode
| Globrix property information: Postcode of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bedrooms
| Globrix property information: Number of bedrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.bathrooms
| Globrix property information: Number of bathrooms the property has
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.type
| Globrix property information: Type of property e.g. 'semi-detatched house'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.condition
| Globrix property information: Condition of the property e.g. 'renovated'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.features
| Globrix property information: Features of the property e.g. 'double glazing'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.outsidespace
| Globrix property information: External features of the property e.g. 'garden'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.parking
| Globrix property information: Parking available for property e.g. 'parking for 2 cars'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.period
| Globrix property information: Period of the property e.g. 'victorian terrace'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.poa
| Globrix property information: If the property price is only available on application
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.tenure
| Globrix property information: The tenure of the property e.g. 'leasehold'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.underoffer
| Globrix property information: Indicates if the property is under offer
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.priceproximity
| Globrix property information: The region of the attached price e.g. 'guide price of'
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.latitude
| Globrix property information: The latitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|-valign="top"
| globrix.longitude
| Globrix property information: The longitude of the property
| [http://content.globrix.com/web-tools/8-technical-guide/74-what-are-globrix-meta-tags-and-how-can-i-use-them FAQ About the Globrix meta tags.]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-07-28T06:33:06Z

Hsivonen: /* Registered Extensions */ Fix formatting error

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

|-valign="top"
| dcterms.creator
| An entity primarily responsible for making the resource. Examples of a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword <code>author</code>
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the <code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-07-28T06:32:11Z

Hsivonen: /* Registered Extensions */ Register dc.date.issued

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal
|-valign="top"

|-valign="top"
| dc.date.issued
| Date of publication for Google News. The format of the content is YYYY-MM-DD or YYYY-MM-DDThh:mm:ssTZD.
| [http://www.google.com/support/news_pub/bin/answer.py?answer=93994 Google News documentation]
| <code><time pubdate></code>, <code>dcterms.issued</code>
| Proposal

| dcterms.creator
| An entity primarily responsible for making the resource. Examples of a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword <code>author</code>
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the <code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-07-28T06:25:34Z

Hsivonen: /* Registered Extensions */ Sort the registrations by Unicode code point

This page lists the allowed extension values for the name="" attribute of the <meta> element in HTML5. You may add your own values to this list, which makes them legal HTML5 metadata names. We ask that you try to avoid redundancy; if someone has already defined a name that does roughly what you want, please reuse it. Also, please be sure to include ''all'' the items [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names required by the spec] ''including a link to a specification'' that specifies the keyword ''as an HTML meta keyword''. Note that URL-valued properties must not be registered as meta names but should be registered as [http://microformats.org/wiki/existing-rel-values#HTML5_link_type_extensions rel keywords] instead. Also note that changes to this registry may not be reflected in validators in real time.

== Registered Extensions ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status

|-valign="top"
| alexaverifyid
| Used to verify ownership of Alexa Search
| [http://www.alexa.com/faqs/?p=188 Alexa FAQ About this meta attribute Reference]
|
| Proposal

|-valign="top"
| apple-mobile-web-app-capable
| Sets whether a web application runs in full-screen mode.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
| Could maybe be assumed when <code>application-name</code> is set?
| Proposal

|-valign="top"
| apple-mobile-web-app-status-bar-style
| Sets the style of the status bar for a web application.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| baiduspider
| Synonym of <code>robots</code> for targeting Baidu only.
| [http://www.baidu.com/search/robots_english.html Baidu documentation]
|
| Proposal

|-valign="top"
| csrf-param
| Cross-site request forgery protection parameter for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal

|-valign="top"
| csrf-token
| Cross-site request forgery protection token for Ruby on Rails
| [http://apidock.com/rails/ActionView/Helpers/CsrfHelper/csrf_meta_tag Rails API]
|
| Proposal
|-valign="top"

| dcterms.creator
| An entity primarily responsible for making the resource. Examples of a Creator include a person, an organization, or a service.
| [http://dublincore.org/documents/dcmi-terms/#terms-creator DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| In some cases redundant with the HTML built-in keyword <code>author</code>
| Proposal

|-valign="top"
| dcterms.description
| An account of the resource. Description may include but is not limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-description DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>description</code>
| Proposal

|-valign="top"
| dcterms.issued
| Date of formal issuance (e.g., publication) of the resource. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-issued DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| <code><time pubdate></code>
| Proposal

|-valign="top"
| dcterms.language
| A language of the resource. Recommended best practice is to use a controlled vocabulary such as RFC 4646 [RFC4646].
| [http://dublincore.org/documents/dcmi-terms/#terms-language DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| Redundant with the <code>lang</code> attribute on the <code>html</code> element. (Browsers pay attention to the <code>lang</code> attribute but not <code>dcterms.language</code>)
| Proposal

|-valign="top"
| dcterms.modified
| Date on which the resource was changed. (DC doesn't spec a date format but the established practice is YYYY-MM-DD.)
| [http://dublincore.org/documents/dcmi-terms/#terms-modified DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
|
| Proposal

|-valign="top"
| dcterms.subject
| The topic of the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-subject DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| HTML built-in keyword <code>keywords</code>
| Proposal

|-valign="top"
| dcterms.title
| A name given to the resource.
| [http://dublincore.org/documents/dcmi-terms/#terms-title DCMI Metadata Terms] mapped according to [http://dublincore.org/documents/dc-html/ Expressing Dublin Core metadata using HTML/XHTML meta and link elements]
| The HTML element <code>title</code>
| Proposal

|-valign="top"
| es.title
| Object Title, where this is not the TITLE or H1 tag content, but the resource title
| [http://www.eibs.co.uk/reference/ EIBS EasySite CMS - Content Attributes Reference]
| dcterms.title
| Proposal

|-valign="top"
| format-detection
| Enables or disables automatic detection of possible phone numbers in a webpage in Safari on iOS.
| [http://developer.apple.com/library/safari/#documentation/appleapplications/reference/SafariHTMLRef/Articles/MetaTags.html Apple Safari HTML Reference]
|
| Proposal

|-valign="top"
| geo.placename
| Defines name of geographic place to which page is related to. Example:
<meta name="geo.placename" content="Auwaldstraße 11, 79110 Freiburg im Breisgau, Deutschland">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.position
| Defines geographic position to which page is related to. Example:
<meta name="geo.position" content="48.02682000000001;7.809769999999958">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft]
|
| Proposal

|-valign="top"
| geo.region
| Defines name of geographic region to which page is related to. Content is specified by ISO-3166. Example:
<meta name="geo.region" content="DE-BW">
| [http://tools.ietf.org/html/draft-daviel-html-geo-tag-08 IETF Draft] [http://en.wikipedia.org/wiki/ISO_3166 ISO-3166]
|
| Proposal

|-valign="top"
| google-site-verification
| Used to verify ownership for Webmaster Tools.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812 Google documentation]
|
| Proposal

|-valign="top"
| googlebot
| Synonym of <code>robots</code> for targeting Googlebot only.
| [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=93710 Google documentation]
|
| Proposal

|-valign="top"
| msapplication-task
| '''"Jump List" or "Pinned Sites" in Windows 7'''
Jump List items act as entry points into the website even when the browser is not running. A Jump List can contain commonly used destinations and tasks. Some items apply to the whole site, and some apply only to specific users.
For example, to add a single task called "Check Order Status" specify a meta element in the head of your webpage, as follows:
<META name="msapplication-task" content="name=Check Order Status;
action-uri=./orderStatus.aspx?src=IE9;
icon-uri=./favicon.ico" />
| [http://msdn.microsoft.com/en-us/library/gg491725(v=vs.85).aspx Tasks in Jump List]
|
| Proposal

|-valign="top"
| msvalidate.01
| One of the verification elements used by Bing.
| [http://onlinehelp.microsoft.com/en-us/bing/hh204490.aspx Bing Webmaster Tools]
|
| Proposal

|-valign="top"
| norton-safeweb-site-verification
| Used to verify ownership of Website for Norton SafeWeb.
| http://safeweb.norton.com/help/site_owners#verification_tips Norton SafeWeb Help Documentation]
|
| Proposal

|-valign="top"
| rating
| The Restricted to Adults label (RTA) provides a way for adult oriented websites to indicate that their content is off limits to children. RTA was introduced in 2006 and is currently used by a large number of adult web content providers. RTA is recognized by all major parental control filters.
Example:
<meta name="RATING" content="RTA-5042-1996-1400-1577-RTA" />
| [http://www.rtalabel.org/index.php?content=howto RTA documentation]
|
| Proposal

|-valign="top"
| rights-standard
| The purpose is to enable search engines and other cataloging services to compile the types of rights allocated to the work. (Does any search engine actually implement this? [[User:Hsivonen|hsivonen]] 07:34, 14 July 2011 (UTC))

'''This keyword does not provide, remove or alter any legal protections or designations.'''

Format:
<pre><meta name="rights-standard" content="element id;rights" /></pre>

* element id - the HTML Element ID of the item these rights apply to
* rights - what rights are assigned to the item
** "pd" - Public domain
** "cc by-sa" - Creative Commons Attribution
** "cc by-nd" - Creative Commons NoDerivs
** "cc by-nc" - Creative Commons Attribution-NonCommercial
** "cc by-nc-sa" - Creative Commons Attribution-NonCommercial-ShareAlike
** "cc by-nc-nd" - Creative Commons Attribution-NonCommercial-NoDerivs

| [http://sites.google.com/site/metarightsstandard/ Spec]
|Redundant with [http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#licensing-works Microdata vocabulary for licensing works].
|Proposal

|-valign="top"
| robots
| A comma-separated list of operators explaining how search engine crawlers should treat the content. Possible values are "noarchive" to prevent cached versions, "noindex" to prevent indexing, and "nofollow" works as the link rel value with the same name. This meta name is already supported by every popular search engine. The content value "NOODP" has been offered elsewhere, so I'm proposing it here. It blocks robots from using [http://www.dmoz.org Open Directory Project] descriptions of a website instead of Web pages' own meta descriptions. It may have been introduced by Microsoft. The content value "NOYDIR" has been offered by Yahoo, so I'm proposing it here. It blocks Yahoo's robot from using the Yahoo directory's descriptions of a website instead of Web pages' own meta descriptions. Whether any other robot supports this is unknown but possibly no other search engine uses Yahoo's directory anyway.
| [http://www.robotstxt.org/wc/exclusion.html#meta Robots exclusion protocol], NOODP value: [http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264 Google], [http://help.yahoo.com/l/us/yahoo/search/indexing/indexing-11.html Yahoo], NOYDIR value: [http://ysearchblog.com/2007/02/28/yahoo-search-support-for-noydir-meta-tags-and-weather-update/ Yahoo], as accessed 4-28-09
|
| Proposal

|-valign="top"
| slurp
| Synonym of <code>robots</code> for targeting Yahoo! only.
| [http://help.yahoo.com/l/au/yahoo7/search/indexing/indexing-11.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| teoma
| Synonym of <code>robots</code> for targeting Teoma and Ask.com only.
| [http://about.ask.com/en/docs/about/webmasters.shtml Ask.com documentation]
|
| Proposal

|-valign="top"
| verify-v1
| Legacy verification for Google Sitemaps.
| [http://sitemaps.blogspot.com/2006/05/more-about-meta-tag-verification.html Inside Google Sitemaps: More about meta tag verification]
|
| Proposal

|-valign="top"
| viewport
| Provides a way for documents to specify (using markup rather than CSS) the size, zoom factor, and orientation of the viewport that is used as the base for the document's [http://www.w3.org/TR/CSS21/visudet.html#containing-block-details initial containing block]. The following properties can be used in the value of the <code>content</code> attribute:
* width
* height
* initial-scale
* minimum-scale
* maximum-scale
* user-scalable
Examples:
<meta name="viewport" content="initial-scale=1.0">
<meta name="viewport" content="width=480, initial-scale=2.0, user-scalable=1">
For more details, see the [http://dev.w3.org/csswg/css-device-adapt/#viewport-meta-element Viewport META element] section of the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification.
| For <code>meta</code> elements that have a <code>name</code> attribute whose value is <code>viewport</code>, the [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] draft specification defines the recognized properties for the <code>content</code> attribute>, as well as an algorithm for parsing the value of that attribute.
|
| Proposal

|-valign="top"
| wt.cg_n
| '''Name of the Content Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_n" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.cg_s
| '''Name of Content Sub-Group'''
Used to configure the appropriate Webtrends advanced feature. These are just some of the more popular ones. These appear in your META tags. – showing you the web page, the source (meta tag), the log files entry and the subsequent WT report.
Example:
<meta name="wt.cg_s" content="My content">
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ac
| '''Advertising Click parameter'''
When a visitor to your site clicks on an ad, that action is referred to as an Ad Click. The following META tag tracks advertising clicks:
<META NAME="WT.ac" CONTENT="name">
Defines the name of the advertisement clicked to reach a particular web page. The Ad Click must contain an external redirect back to the client. The redirect needs to include the necessary code to generate a hit to the SDC server. You can designate multiple Advertising Clicks using semicolons.
Examples:
<a href="file111.html?WT.ac=CONTENT111">
<a href="file222.html?WT.ac=CONTENT222">
The name of the advertisement clicked to reach a particular web page. To capture this information with DCS, the Advertising Click must contain an external redirect back to the client. The redirect needs to

include the necessary code to generate a hit to the DCS. The maximum length for each name is 64 bytes.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.ad
| '''Advertising View parameter'''
Visitors often view advertisements that they do not necessarily click on. You can use On-Site Advertising to determine the number of visitors to your web site who view particular ads. With this feature you can produce advertising reports for each of your clients.
If you are selling advertising space on your web site, for example, you can collect traffic statistics to help determine pricing schedules.
The following META tag tracks advertising views:
<meta name="WT.ad" content="My content">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.mc_id
| '''Identifies the ID of the marketing campaign'''
To attract new students, a university launches a marketing campaign by sending recruitment email to all graduating high school seniors in a metropolitan area. The email links to a special landing page in the university’s web site, containing the following META tag to track marketing campaigns.
Example:
<META NAME="WT.mc_id" CONTENT="1X2GG34">
You may use this parameter on the URL.
Example:
<a href="link?WT.mc_id=1X2GG34">
The Campaign ID 1X2GG34 represents recruits to be contacted by email
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| wt.sv
| '''Tracking Servers parameter'''
If your site is hosted on multiple servers, a server cluster, or a server farm, and you want to evaluate the performance of your load balancer, Webtrends can track page views for each server. To do so, populate the following META tag on all pages on each server:
Example:
<meta name="WT.sv" content="My Server">
Defines the name of the machine that serves the web page. If you have two servers (Server1 and Server2), you would make two copies of the META tag and designate CONTENT=“Server1” for deployment to pages on the first server and CONTENT=“Server2” for deployment to the same pages on the second server.
For a server farm, you can extract the value of the built-in server name and dynamically assign it to the
META tag using server-side scripting.
Example:
<meta name="WT.sv" content="Server1">
<meta name="WT.sv" content="Server2">
An Ad View occurs when a visitor views a page containing an ad. An ad is a link or graphic that contains an Ad Click parameter in the query portion of it's URL.
| [https://tagbuilder.webtrends.com/Help/Miscellaneous/AdSearch.aspx?keepThis=true&TB_iframe=true&height=450&width=650 About WT.ad].
|
| Proposal

|-valign="top"
| wt.ti
| '''Tracking Page Titles'''
You may want to modify a page title before sending it to Webtrends in the following cases:
* You are dealing with dynamic content pages identified by URL parameters, and the page title represents the title of the base URL page rather than the dynamic content page.
Unless you modify the page titles, all pages have the same title in the reports.
* All pages have been assigned the same title, for reasons of style or company policy.
Even though URLs are displayed in addition to page title, the entire URL cannot be depended upon to distinguish one page from another.
Use server-side scripts to change the title to something that reflects the content of the pages so that you can identify them in reports. Next, pass the customized page titles to Webtrends, using the following META tag:
<META NAME="WT.ti" CONTENT="title">
Defines the name of the title for this page.
| [http://product.webtrends.com/WRC/OnDemand/ResourceCenter/rc/Library/PDF/IGOD/WebTrendsAnalyticsOnDemandImplementationGuide.pdf Webtrends Parameters]
|
| Proposal

|-valign="top"
| y_key
| Used to verify ownership for Yahoo! Site Explorer
| [http://help.yahoo.com/l/us/yahoo/search/siteexplorer/siteexplorer-06.html Yahoo! documentation]
|
| Proposal

|-valign="top"
| yandex-verification
| Used to verify ownership for Yandex Webmaster.
| [http://help.yandex.ru/webmaster/?id=995300#995356 Yandex Webmaster ownership verification]
|
| Proposal

|}

== Proposals that don't meet the [http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#other-metadata-names requirements] for a registration ==

Note that these proposals can be moved back to the registry table if the problems listed in the rightmost column of this table are addressed.

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to specification
! Synonyms
! Status
! Registration requirement failure

|-valign="top"
| audience
| To aid search engines in classifying and to aid directory compilers, an audience most appropriate for the page may be suggested. Subject matter may not be a good clue; for example, an analysis of children's literature may be directed to teachers. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated. Singular and plural forms have the same meaning. Recognized values: -- "all" and "everyone", which have the same meaning -- "adult" and "mature" have the same meaning and are for content that only adults may access, but no one responsible for preventing a nonadult or the immature from accessing the page or its content should rely on either or both of these values to do so without other means (not the same as "grownup", which see) -- "child" and "juvenile", which have the same meaning -- "teen" -- "grownup" is not identical to "adult" or "mature" in not implying a precise boundary but is approximately any person who may be able to understand and apply the content (e.g., car driving instruction that may be read by a minor not yet old enough to drive a car but who would likely benefit from somewhat early exposure to the instruction) -- "parent" to include guardian and temporary caregiver -- "teacher" to include professor and ad hoc instructor -- "elementary school student" to include any student below high school -- "high school student" -- "elhi" to include any student in elementary school through high school -- "college student" including graduate and professional school -- "business" including management, finance, and prospective customers (this includes e-commerce and investor sites) -- "health" including any health care provider including alternative and ad hoc -- "patient" for any health care recipient -- "lawyer" including judge, paralegal, and jailhouse lawyer -- "law client" for any prospective recipient of a lawyer's service (not usually a social work client) with ''lawyer'' including paralegal and jailhouse lawyer but not necessarily judge -- "craft" for any craftworker including laborer and artisan -- "artist" including musician, actor, dancer, and sculptor and including creator and performer -- "military" including paramilitary -- "news" including any consumer of rapidly-developing news -- "introductory" and "beginner", which have the same meaning -- "intermediate" and "midlevel", which have the same meaning -- "advanced" and "advance", which have the same meaning -- "scholarly" and "scholar", which have the same meaning -- "popular" generally referring to a writing style -- "older" including retiree -- "institution" including from corporation to conspiracy (such as for management advice) -- "government" including agencies and prospective politicians -- values using any integer or single-digit decimal in the form of "grade 8" or "grade 6.4" including to refer to a reading comprehension level (this generally will not exceed 12 and might be meaningless above 20 so higher values may be interpreted as the highest meaningful value) -- "viewers" for when content (such as a movie) is intended almost entirely to be seen rather than read -- "listeners" for when content (such as music) is intended almost entirely to be heard rather than read but not generally including text-to-speech support -- "tts", "text-to-speech", or "text to speech", which three have the same meaning and which are for a page that has substantial support for TTS or that will be readily understood through TTS without need for such support (TTS is often aided by, e.g., pre-resolving pronunciation ambiguities in page coding) -- values using any numbers in the form of "3-6 years old", whether a range or a single-number value -- values using any decade in the form of "born in 1970s" Unrecognized values such as "botanists", "Texans", and "writers who use red ink" may be used but at a risk that a search engine or directory editor will either fail to recognize it or will interpret it in unpredictable ways, or will in the future. Spellings that are erroneous or slightly different from a recognized value may be interpreted by a search engine or directory editor as representing a recognized value. The absence of the keyword defaults to a value of "all" but without overriding another indication arrived at by other means.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| bot-. . .
| Robot owners, to allow page authors access to robotic capabilities, e.g., to deny them, should prefix "bot-" to the name of their robot, especially for proprietary bots. Example: If a robot were to be named "dullbucklequiz", the name in the meta element would be "bot-dullbucklequiz". The value "bot-" alone represents all bots so prefixed, like a wildcard. Arguably, there's no need for a list here of any specific bots if http://user-agents.org or http://www.botsvsbrowsers.com/ (and perhaps other sites) is reliable.
|
|
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| created
| The datetime at which the document was created. The value is an ISO8601 date. The date MUST follow the [http://www.w3.org/TR/NOTE-datetime W3C Profile of ISO 8601] with a granularity of "Complete date:" or finer. The [http://www.bbc.co.uk/guidelines/futuremedia/desed/previousversions/searchmetadata_vs_1_0.shtml#metadata BBC] use this name.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| creator
| The creator is an off-Web or pre-Web creator of a work for which an author authored a Web page, so that the creator and the author may be different people. Searching for one content creator's work requires a standard robot-parsable format for the information. A personal name, institutional name, or other text entry is permissible. One element represents only one creator. Multiple creators are to be represented with multiple tags. Search engines may index by any component of a name, so a content creator need only enter a name once in one first-last or family-given order (e.g., Pat Thunderbird or Thunderbird, Pat, but not requiring both).
| [[Talk:MetaExtensions#Re:_Proposed_'creator'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| msnbot
| Synonym of <code>robots</code> for targeting Bing only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| ia_archive
| Synonym of <code>robots</code> for targeting Internet Archive and Alexa only.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage
| The author may be the best expert on which time frame is most relevant to the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers that may focus on the 1800s but mention 1731 and 1912 perhaps unimportantly. The value for this keyword is a date or time -- not a range and not vague, for which other keywords are proposed -- in a format in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, all the values so appearing are determinative. Multiple values are to be expressed with separate meta elements lest the note be revised in the future in a way incompatible with comma-separating a list.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-end
| This is identical to the keyword datetime-coverage except that it represents only the end. If this keyword is used without datetime-coverage-start (also proposed), its value is interpreted as ending a range without a start. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the end of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-end=1865, datetime-coverage-start=1914, datetime-coverage-end=1918, and datetime-coverage-start=1862, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-start
| This is identical to the keyword datetime-coverage except that it represents only the start. If this keyword is used without datetime-coverage-end (also proposed), its value is interpreted as starting a range without an end. Should this keyword appear more than once, all the values so appearing are determinative, in which case each represents the start of a different range assumed to be nonnesting. Example: If four elements happen to be in the order of datetime-coverage-start=1862, datetime-coverage-start=1914, datetime-coverage-end=1865, and datetime-coverage-end=1918, assuming proper formatting, the ranges should be interpreted as 1862-1865 and 1914-1918.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| datetime-coverage-vague
| This is identical to the keyword datetime-coverage except that its value is not necessarily crisp. This keyword should be used only when datetime-coverage, datetime-coverage-start, and datetime-coverage-end are inappropriate, but there's no ban on using all four. Any text without a comma can be the value (e.g., Pleistocene, 1820s, Tuesdays, or before we were born); multiple values are comma-separated. If this keyword is used with datetime-coverage, datetime-coverage-start, or datetime-coverage-end, the vague value should be exploited along with the value/s for the other keyword/s. Should this keyword appear more than once, all are determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| DC.
| Dublin Core, maintained by Dublin Core MetaData Initiative (DCMI), is an extensive system with some overlap with non-DC names. This reserves all strings that begin with DC and a dot. ''Not true; DC-HTML doesn't use hardwired prefixes, but defines the prefixes using link/@rel="scheme.prefix"''
| [http://www.DublinCore.org DCMI]
|
| Incomplete proposal
| Tries to register a space of names instead of enumerated names

|-valign="top"
| dir-content-pointer
| When several pages in a directory include main content, a table of contents, an index, and the like, a search engine may be able to organize results more usefully by identifying which is which with a standard vocabulary, helpful when different publishers use different conventions when displaying or printing content. A value is free-form case-insensitive text without a comma and optionally with a trailing number. Multiple values are to be comma-separated (multiple values are appropriate when one document serves multiple purposes). Singular and plural forms have the same meaning. Recognized values, which are pointer types to which numbers may be suffixed, are limited to "start" meaning 'the first page that should be seen by a user' (this may be anywhere in the directory and anywhere within content), "toc" meaning 'table of contents', "intro" including introductions, forewords, prefaces, and tables of figures, "abstract", "main", "bibliography" and "biblio", which have the same meaning, "index" which may mean 'sitemap' or not, "afterword" and "update" which have the same meaning and need not actually update, "credit" meaning 'credits and acknowledgments', and "author bio" meaning 'author's biography', including any information about the author including credentials and contact information. The number suffix may be spaceless or not. When numbers are suffixed, a search engine or directory should arrange like items in numerical order in the results, with unnumbered items following like items that are numbered, e.g., intro 1, intro 2, main 1, main 2, main, main, and so on. Each directory and each subdirectory has its own sequence.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
|expires
|<code>meta name='expires'</code> defines the expiration date of the page. This can be used for web pages in preparation for an upcoming event, e.g. a registration form for an exposition or competition, or other cases with a pre-set date when the document will no longer be valid, e.g. a product offer in a special sale or a support page for a product known not to be supported anymore from a given time onward.

Search engines should respond to this meta tag in a reasonable way, i.e. by removing the page from their main search results after the expiration date (possibly still returning the result in a special search for expired pages as long as the page exists and is not explicitly excluded via <code>robots.txt</code> or <code>meta name='robots'</code> etc.) or simply by indicating to the user that this result is out-of-date.

The content attribute should define the expiration date in accordance with http://www.w3.org/TR/NOTE-datetime . The meta tag should not be used for pages without expiration date. However, for historical reasons, search engines should also interpret other date formats where possible and should be prepared to find values such as "", "0", "no" and "never". Such non-date values are to be interpreted as no expiration date.

Correctly formatted example:
<code><pre><meta name='expires' content='2012-12-31T23:59Z'></pre></code>

This tag is not to be confused with and has a different meaning than <code>meta http-equiv='expires'.</code>
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| format-print
| This is to allow a user agent to inform an operating system or a printer driver of the preferred print medium, such as the paper size. A value is free-form case-insensitive text without a comma. Multiple values are to be comma-separated (multiple values might be appropriate because standard paper sizes vary around the world). Singular and plural forms have the same meaning. Recognized values are limited to "letter", "A4", "legal", "A5", "B5", "monarch", "envelope 10" meaning size #10, "envelope 6-3-4" meaning size #6 3/4, values with integers and decimals in the form of "8.5 x 11" or "8.5x11" in which spacing of the "x" does not affect meaning, "paper", which means 'paper of the default color (usually white) and weight (usually 20-lb. stock)', "white", "yellow", "pink", "blue", "green", "violet", or "multicolor", which means a medium of the given color or mixed, "letterhead", "p2 letterhead" meaning 'letterhead intended for any page except the first', "watermark" meaning a 'special watermark such as an organization's own', and "plain" meaning 'not preprinted and not letterhead (it may have a paper manufacturer's watermark not related to letterhead)'. Omitting "paper" when another recognized value is given defaults to an implied meaning of 'paper' with the other value; e.g., "letter" means 'letter paper'; the same principle applies to a medium's color (the default being white for paper and colorless for transparency) and plainness or lack thereof (the default being plain). Other values should be proposed before being recognized here. Label sizes should be proposed here for labels that are not on backing sheets that fit one of the recognized values, e.g., labels on narrow rolls. Blueprint paper sizes should be proposed here. Media other than standard paper, such as onion skin, heavier paper, card, and clear or color transparency, should be proposed here. The user agent may, with the user's or user sysadmin's permission (as by a menu-driven default), interpret a value to offer an alternative the user might accept and software and firmware other than the UA may interpret a value to the same end with or without permission, so this keyword is only suggestive; e.g., "letter" may be interpreted as "A4". The absence of the keyword defaults to a value determined by other than the page, e.g., by the printer driver or the user agent.
| [[Talk:MetaExtensions#Re:_Proposed_'format-print'_MetaExtension|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| geographic-coverage
| The author may be the best expert on the geographic relevance of the content. Leaving that to search engine analysis may be too chancy without search engine optimization, which analysis is difficult to apply by algorithm to, e.g., historical papers and epidemiological studies which may mention locales only once. Absence of the keyword defaults to a value of world (not universe), unless the search engine chooses to interpret the page or larger unit for some other value, probably based on other than just contact information given in the website. The value for this keyword is a semicolon-separated list of one or more place-values, the order of which do not matter. One place-value will use commas to separate, in order, an optional standard natural language symbol applicable to the place-value (when omitted the language applicable to the page will control), a place-class, one or more place-subclasses if any, and one or more place name parts (where, e.g., in "Cape Town, South Africa", "Cape Town" is a place name part but "Town" is not). Spaces after semicolons and commas are optional; spaces within place-values are present when required for each place-value (e.g., "Quezon City", not an invented "QuezonCity"). To distinguish names that might otherwise be too similar, place-classes, all lower-case and hyphenatably spaceless, include ''outer-space'', ''region'' (on Earth and crossing or larger than a nation, e.g., southern hemisphere, polar region, temperate zone, or Asia), ''intntl-water'' (an 'international water body'), ''intntl-agcy'' ('international agency' or 'international collection', e.g., all U.N. member nations), ''nation'', ''within-nation'' (limited to only one political level down from nation, e.g., state, province, territory, possession, city not included within other political units of a nation, or any comparable unit), ''city'' (including town, village, hamlet, and any comparable political unit below the level of ''within-nation''), ''addr'' (including address, full-length street, building, institution, and neighborhood without political boundaries), ''pol-unit'' (''pol'' abbreviating 'political') (e.g., a place of disputed nationhood), ''hist-pol-unit'' (''hist'' abbreviating 'historical') (e.g., the Roman Empire), ''feature'' (e.g., river), ''num'' (e.g., latitude and longitude or outer-space equivalent in numbers), and ''ethereal'' (including thealogical/theological, fictional including from modern popular entertainment, and ancient secular mythical, but not including that which is asserted to be a state of mind or existence but not a place, such as nirvana). (Example for one hypothetical page: name="geographic-coverage" content="region, sub-Saharan Africa; nation, Panama; city, Panama, Panama; within-nation, Sao Paulo, Brazil; city, Sao Paulo, Sao Paulo, Brazil; within-nation, Mississippi, United States of America; region, Middle East; region, Midwest, United States of America; hist-pol-unit, Northwest Territory, United States of America; feature, river, Indus; outer-space, Indus; ethereal, ultima Thule; ethereal, Heaven; ethereal, Flatland; ethereal, Valhalla; en-US, addr, Hotel Valhalla, Fredrikstad, Norway; es, nation, Espana" (Indus is both a river and a constellation, illustrating the need for place-classes)). Ambiguity of place-values should be avoided despite convenience in coding because search engines may each interpret them as they see fit, e.g., it would be hard for an engine to distinguish New York from New York. For consistency of spelling, several authority lists should be settled upon, with legal, well-known, and disputed names and common abbreviations all being acceptable; but I'm not proposing one here now (relying on IANA's ccTLD list might be too complex to implement and still assure coding consistency, e.g., occasionally ccTLDs can be phased out and off of IANA's list) (a standard vocabulary possibly usable here is the [http://www.getty.edu/research/conducting_research/vocabularies/tgn/index.html Getty Thesaurus of Geographic Names Online], subject to licensing and charset choice); and promulgating authority lists may best be done publicly by search engine managements, who may disagree with each other. Allowing Unicode for non-Roman alphabet-using locales is desirable, but at present that may raise technical problems, including computer security issues, that are not yet readily soluble.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| keywords-not
| A comma-separated list of negative keywords that distinguish a closely-related theme from this page's true theme, to support Boolean NOT searches often more realistically than visible text can, especially when both themes share the same lexicon. If keywords is no longer a supported name for a meta element, keywords-not is superfluous; however, debate has been revived on whether keywords should be supported or not; see the keywords entry in this Wiki.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6609 W3C Bug 6609]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-datetime
| Better ranking in search engine results for recency or relevance to an event date would be aided by a standard format robots can parse. Users would save search time by not having to load many pages to find which ones are new or date-relevant. To supply a consistent and known format, the value for this keyword is a date-time expression formed in accordance with http://www.w3.org/TR/NOTE-datetime (albeit a note that's at W3C only for discussion). Any of the six levels of granularity in that note are acceptable, such as expressing only a year. Should this keyword appear more than once, only the first one so appearing is determinative.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| page-version
| Pages may be revised several times daily. While date-time given to a granularity of a fraction of a second would often suffice, when a page has to be approved more than once before posting, any or no such time may be correct (without this keyword, a comment could be necessary but probably not parsable by an engine). In addition, versions regardless of date may show consecutiveness and can replace a date that must be vague. In that case, a version number may be more useful for searches and so a robot-parsable format is needed. The keyword's value is stated in ASCII digits, is any nonnegative base-10 rational number expressed as an integer or a decimal, with any number of decimal places allowed, and may be padded with any number of leading zeros to support extraction for ASCII sorting. Should this keyword appear more than once, only the first one so appearing is determinative. The versions 0 and 0.''n'', with ''n'' being to any number of places, signify beta versions, i.e., drafts, in the tradition of beta software, while versions 1 and higher ordinarily signify final-release versions. After a final-release version is released, a draft of a later version is not given a version number of 0 or 0.''n'', but is numbered higher than the last final-release version. It is suggested to page authors that draft status, if applicable, be shown in the visibly displayed text of the page, rather than that this meta tag be relied upon as the sole notice of draft status, as it may be inadequate notice if alone. To assign a low page-version such as 0.''n'' or 1, the page's URL, if static, may be used as the relevant premise. Thus, if a page is copied or moved to a new URL, the author may choose to restart page-version numbering from 0.''n'' or 1. If a page's URL is dynamic, e.g., if created on the fly from a script, the page author may prefer to use as the relevant premise for assigning a low page-version such as 0.''n'' or 1 the URL of the script or other technology that generates the dynamic-URL page, placing this meta element containing this attribute within the script or other technology, not within the generating page's head element (the generating page's head element may have its own meta element with this attribute describing the generating page). If one page containing the script or other technology that generates another page has more than one means for generating dynamic-URL pages, each means should contain its own meta element with this attribute. Page-version is thus largely independent of the page's date, although both would likely advance roughly in parallel.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| publisher
| Searching for one content publisher's or page publisher's work requires a standard robot-parsable format for the information. This often differs from creator or author when the publisher is an institution. An institutional name, personal name, or other text entry is permissible. One element represents only one publisher. Multiple publishers are to be represented with multiple tags, although multiple publishers are less common than multiple authors or creators; multiplicity is more likely for a legal name and a well-known name. Search engines may index by any component of a name, so a publisher need only enter a name once in one order.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| referrer
| Developers wish to control the sharing of referrer information with linked resources and followed links at the meta level. It's sometimes desirable to share referrer information from secure to non-secure resources. The proposal is to add:

<code><pre><meta name="referrer" content="never|default|always"></pre></code>

Where the value of the '''content''' attribute is:
* '''never''': No referrer information is leaked when following a links or requesting resources.
* '''default''': Include referrer information in non-secure context or for HTTPS resources with the same origin.
* '''always''': Include referrer information when following all links and requesting any resources.

Since <code><meta name="referrer" content="never"></code> is redundant with a proposed <code><link rel="nofollow"></code>, the <code><link rel="nofollow"></code> proposal should be supplanted with this one, which provides more robust control.
|
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| resolutions
| Authoring web sites to use resolution independent images that display beautifully on high-resolution displays should be made as easy as possible for developers and should not require JavaScript to accomplish.

To accomplish this, I propose a new HTML Meta Tag, <code>resolutions</code>, that can be used to specify that high-resolution versions of images linked to from the page are available and that the browser should use them in place of the lower-resolution default images if it detects that a user is using a high-resolution screen. The resolutions meta tag lists the device-pixel ratios supported by images in the page.

So, for example…

<code><pre><meta name="resolutions" content="2x"></pre></code>

… means that the developer is telling the browser that she has created 2x resolution images for the images linked to from the current page and named them with a @2x suffix.

To illustrate, if her image tag is as follows…

<code><pre><img src="/images/flower.jpg" alt="A flower"></pre></code>

… then she has two image files under /images: the low-resolution default (flower.jpg), and a higher-resolution (200%) version named flower@2x.jpg.

(This is the same naming convention already used by Apple in its Cocoa Touch framework for automatically loading in higher-resolution versions of images.)

Based on the meta tag, if the browser detects that the user is running at a <code>min-device-pixel-ratio</code> of 2.0, it will automatically ask for the 2x version of the image (flower@2x.jpg) instead of the default image as specified in the image tag.

Finally, so as not to flood external sites with high-resolution image requests, this functionality would only work for local images specified via relative links.

Multiple resolutions

The resolutions tag can also contain a list of supported device-pixel ratios so as to support even higher-resolution displays when and if they become available in the future.

For example:

<code><pre><meta name="resolutions" content="2x, 4x, 8x"></pre></code>

In this case, the developer would provide 2x, 4x, and 8x versions of all images. So, in the running example, she would make flower.jpg, flower@2x.jpg, flower@4x.jpg, and flower@8x.jpg.

Advantages

The advantages of this approach are several:

<ol>
<li>Makes it very simple for developers to support high-resolution displays like the iPhone 4's Retina screen</li>
<li>Does not require JavaScript</li>
<li>Does not change the default way that things work (if the meta tag is not specified, the browser simply behaves as it always has).</li>
</ol>

| [http://aralbalkan.com/3355 Proposal for native browser support of high-resolution image substitution]
[http://aralbalkan.com/3331 How to make your web content look stunning on the iPhone 4’s new Retina display]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| rights
| As a page effectively appears in at least two forms, usually one as interpreted and displayed on a device and the other as source code, arguably intellectual property rights that must be asserted must be asserted in ways understandable in both contexts. For example, &copy; is a raw representation that may legally fail as part of copyright notice to someone seeing source code and not the display, important when someone wants to copy source code for use elsewhere and may rely on a defense of innocent infringement (at least in U.S.). While such assertions can be made in a comment element, it may be helpful to have a tag that search engines can parse and index verbatim. The value may include standard and nonstandard notices, invocations of licenses such as GFDL and ASCAP, and any other information. Content is defined as free-form, leaving the page author discretion for the entry. Statements in one tag may discuss several portions of the page differently, e.g., with different licenses. More than one license may be offered, along with the page's relationship to all. Not all statements need be license grants. A statement may state whom to ask for reprint permission or may reserve all rights, for example. Only one meta tag with this keyword may be present. Page authors must not use more than one. A UA finding multiple such tags on one page must ignore all of them. The copyright symbol that would be generated by its character entity is not recommended for legal notice in source code when the word 'Copyright' may be used instead, because the entity may be read in raw form, but use is up to the page author. The same concept applies to any intellectual property rights symbol for which a suitable alternative is available, such as for trademark or service mark. ASCII text would not suffice when a name or notice legally may have to be in a non-Roman alphabet, but no alternative may yet exist in HTML5. Search engine storage may impose a length limit, but, because of legal consequences, if the value's length exceeds a given limit the search index should retain or interpret none of it but only refer to it. The content string may only be copied verbatim in its full length, referred to, or ignored. It may not be, for example, paraphrased, truncated, interpreted, or classified except in addition to being copied verbatim in its full length. Ignoring shall not void, nullify, or alter any rights stated in such tag. For the synonymy, ''IP'', ''IP-rights'', and ''IP-right'' are not reserved; while the abbreviation ''IP'' 'intellectual property' is common among attorneys in the U.S., page authors will more likely be computerate, and the abbreviation may be wanted for 'Internet Protocol'.
| [[Talk:MetaExtensions#rights:_why_reversion|Talk]]
|
| Incomplete proposal
| Lacks link to a spec

|-valign="top"
| subj-. . .
| To classify by subject a page's content, a standard subject taxonomy that will be recognized by a search engine or directory will help. Because many such high-quality taxonomies exist, only a prefix is proposed. Over time, particular taxonomies, in print or online, may be recognized here and keywords assigned for each. The keyword will be constructed case-insensitively with subkeywords in the form subj-[nationAbbrev]-[taxonomy]-[edition][-optionalSubedition], e.g., subj-US-MeSH-2009online (perhaps). After "subj-", the second subkeyword will identify the nation where the taxonomy is published or offered as an aid in identifying the taxonomy and does not limit the subject coverage; e.g., a taxonomy published in Japan may be ideal for classifying Canadian botany or Peruvian economy. As subject values may vary between editions of one taxonomy, an edition and optionally a subedition is to be identified in the third and optionally the fourth subkeywords. The subedition, if any, is any update or revision occurring between editions, such that a value drawn from that edition and subedition is stable. The means of identifying edition and subedition should be included in the registration of a keyword. Examples of taxonomies from the U.S. include MeSH (medical) and the Library of Congress Subject Headings. The value identifying a subject for a Web page will be drawn from the cited taxonomy's edition and subedition. If the value should have a style to prevent ambiguity in interpretation, that style is to be registered here for that keyword. Multiple values are expressed with multiple meta elements, one value for each, since comma-separation is probably not compatible with all taxonomies. If a value requires case-sensitivity to prevent confusion, the entry here registering the keyword must accommodate that need with the needs of HTML 5 with an appropriate rule. To that end, a proposal to allow case-sensitivity in meta tags under some circumstances has been offered in the W3C bug reporting system.
| [http://www.w3.org/Bugs/Public/show_bug.cgi?id=6854 W3C Bug 6854]
| subject-. . .
| Incomplete proposal
| Lacks link to a spec, tries to register a space of names instead of enumerated names

|-valign="top"
| MSSmartTagsPreventParsing
| Microsoft introduced into Internet Explorer 6 Beta a feature that some website designers wished to preclude from applying in order to prevent public misunderstanding of their websites. The feature allowed a browser to add information but at a risk that users wouldn't know that it wasn't supplied by the website. This keyword was provided by Microsoft for those of us who wanted it. Its value was "TRUE". Microsoft spelled the keyword with some capitals and the value in all capitals but whether capitalization was required for either is unknown; some opinions vary. Since it need be understood by only one browser, and that one a beta version, full standards compliance should not be assumed, and original case may be required. (This tag is used by Google: "<meta content='true' name='MSSmartTagsPreventParsing'/>" appeared (with internal quote marks as singles) in the source code for <http://googleblog.blogspot.com/2009/04/listening-to-google-health-users.html>, as accessed 4-27-09.) Microsoft has apparently removed this instruction from its website on the ground that the beta version is no longer available and is not supported, but that doesn't assure that some users aren't still using the beta browser, perhaps inadvertently. Therefore, designers may wish to continue using the keyword and value and they are preserved here.
| e.g., [http://www.theregister.co.uk/2001/06/25/web_sites_banish_those_winxp/ The Register (U.K.)], [http://cc.uoregon.edu/cnews/summer2001/summer2001.pdf Univ. Oregon (U.S.) (PDF p. 18)], & [http://trillian.mit.edu/~jc/demo/SmartTagsOff.html John Chambers (U.S.) (job résumé near root)], all as accessed 4-19-09
|
| Incomplete proposal
| Lacks spec, potentially never minted by MS as a meta name (as opposed to a http-equiv value), even if minted by Microsoft, abandoned before shipping in any final release of IE

|}

== Failed Proposals ==

{|border=1 cellpadding=4 cellspacing=0
! Keyword
! Brief description
! Link to more details
! Synonyms
! Status

|-valign="top"
| cache
| This doesn't actually work; use HTTP headers instead. Value must be "public", "private", or "no-cache". Intended as a simple way to tell user agents whether to store a copy of the document or not. An alternate for HTTP/1.1's cache-control; for publishers without access to modifying cache-control.
| none
|
| Unendorsed

|-valign="top"
| no-email-collection
| HTML5 prohibits URL-valued meta names. They should be rel keywords instead. Intended to reference legal policy of web site indicating that harvesting of e-mail addresses on the site is not permitted and in violation of applicable laws such as the CAN-SPAM Act of 2003.
| [https://www.ProjectHoneyPot.org/how_to_avoid_spambots_5.php Project Honey Pot]
|
| Unendorsed

|}

== Process ==

For the "Status" section to be changed to "Ratified", the proposed keyword must be defined by a W3C specification in the Candidate Recommendation or Recommendation state. If it fails to go through this process, it is "Unendorsed".

For more details, see [http://whatwg.org/specs/web-apps/current-work/#concept-meta-extensions the HTML5 specification].

[[Category:Registries]]

MetaExtensions

2011-07-14T07:34:28Z

Hsivonen: /* Registered Extensions */ Note the redundancy with microdata

MetaExtensions

2011-07-14T07:29:50Z

Hsivonen: /* Registered Extensions */ Changing registrations to the canonical case