Abstract

This specification defines the HTML microdata mechanism. This mechanism allows machine-readable data to be embedded in HTML documents in an easy-to-write manner, with an unambiguous parsing model. It is compatible with numerous other data formats including RDF and JSON.

Status of This document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

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The bulk of the text of this specification is also available in the WHATWG Web Applications 1.0 specification, under a license that permits reuse of the specification text.

The working groups maintains a list of all bug reports that the editors have not yet tried to address and a list of issues for which the chairs have not yet declared a decision. These bugs and issues apply to multiple HTML-related specifications, not just this one.

Implementors should be aware that this specification is not stable. Implementors who are not taking part in the discussions are likely to find the specification changing out from under them in incompatible ways. Vendors interested in implementing this specification before it eventually reaches the Candidate Recommendation stage should join the aforementioned mailing lists and take part in the discussions.

Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

The latest stable version of the editor's draft of this specification is always available on the W3C CVS server. There are various ways to follow the change history for this specification:

Browsable version-control record of all changes:

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The W3C HTML Working Group is the W3C working group responsible for this specification's progress along the W3C Recommendation track. This specification is the 25 October 2012 Working Draft.

Work on this specification is also done at the WHATWG. The W3C HTML working group actively pursues convergence with the WHATWG, as required by the W3C HTML working group charter. There are various ways to follow this work at the WHATWG:

• Commit-Watchers mailing list (complete source diffs): http://lists.whatwg.org/listinfo.cgi/commit-watchers-whatwg.org
• Annotated summary with unified diffs: http://html5.org/tools/web-apps-tracker
• Raw Subversion interface: svn checkout http://svn.whatwg.org/webapps/

This specification is an extension to the HTML5 language. All normative content in the HTML5 specification, unless specifically overridden by this specification, is intended to be the basis for this specification.

This document was produced by a group operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

Table of Contents

1. 1 Dependencies
2. 2 Terminology
3. 3 Conformance requirements
4. 4 Introduction
   1. 4.1 Overview
   2. 4.2 The basic syntax
   3. 4.3 Typed items
   4. 4.4 Global identifiers for items
   5. 4.5 Selecting names when defining vocabularies
   6. 4.6 Using the microdata DOM API
5. 5 Encoding microdata
   1. 5.1 The microdata model
   2. 5.2 Items
   3. 5.3 Names: the itemprop attribute
   4. 5.4 Values
   5. 5.5 Associating names with items
   6. 5.6 Microdata and other namespaces
6. 6 Microdata DOM API
   1. 6.1 HTMLPropertiesCollection
7. 7 Other changes to HTML5
   1. 7.1 Content models
   2. 7.2 Drag-and-drop
8. 8 Converting HTML to other formats
   1. 8.1 JSON
9. 9 IANA considerations
10. References

1 Dependencies

This specification depends on the Web IDL and HTML5 specifications. [WEBIDL] [HTML5]

2 Terminology

This specification relies heavily on the HTML5 specification to define underlying terms.

HTML5 defines the concept of DOM collections and the HTMLCollection interface, as well as the concept of IDL attributes reflecting content attributes. It also defines tree order and the concept of a node's home subtree.

HTML5 defines the terms URL, valid URL, absolute URL, and resolve a URL.

HTML5 defines the terms alphanumeric ASCII characters, space characters split a string on spaces, converted to ASCII uppercase, and prefix match.

HTML5 defines the meaning of the term HTML elements, as well as all the elements referenced in this specification. It also defines the HTMLElement and HTMLDocument interfaces. It defines the specific concept of the title element in the context of an HTMLDocument. In the context of content models it defines the terms flow content and phrasing content. It also defines what an element's ID or language is in HTML.

HTML5 defines the set of global attributes, as well as terms used in describing attributes and their processing, such as the concept of a boolean attribute, of an unordered set of unique space-separated tokens, of a valid non-negative integer, of a date, a time, a global date and time, a valid date string, and a valid global date and time string.

HTML5 defines what the document's current address is.

Finally, HTML5 also defines the concepts of drag-and-drop initialization steps and of the list of dragged nodes, which come up in the context of drag-and-drop interfaces.

3 Conformance requirements

All diagrams, examples, and notes in this specification are non-normative, as are all sections explicitly marked non-normative. Everything else in this specification is normative.

The key words "MUST", "MUST NOT", "REQUIRED", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in the normative parts of this document are to be interpreted as described in RFC2119. The key word "OPTIONALLY" in the normative parts of this document is to be interpreted with the same normative meaning as "MAY" and "OPTIONAL". For readability, these words do not appear in all uppercase letters in this specification. [RFC2119]

To eat a kiwi, the user must:
1. Peel the kiwi.
2. Eat the kiwi flesh.

To eat a kiwi:
1. The user must peel the kiwi.
2. The user must eat the kiwi flesh.

4 Introduction

4.1 Overview

This section is non-normative.

Sometimes, it is desirable to annotate content with specific machine-readable labels, e.g. to allow generic scripts to provide services that are customised to the page, or to enable content from a variety of cooperating authors to be processed by a single script in a consistent manner.

For this purpose, authors can use the microdata features described in this section. Microdata allows nested groups of name-value pairs to be added to documents, in parallel with the existing content.

4.2 The basic syntax

This section is non-normative.

At a high level, microdata consists of a group of name-value pairs. The groups are called items, and each name-value pair is a property. Items and properties are represented by regular elements.

To create an item, the itemscope attribute is used.

To add a property to an item, the itemprop attribute is used on one of the item's descendants.

<div itemscope>
 <p>My name is <span itemprop="name">Elizabeth</span>.</p>
</div>

<div itemscope>
 <p>My name is <span itemprop="name">Daniel</span>.</p>
</div>

Properties generally have values that are strings.

<div itemscope>
 <p>My name is <span itemprop="name">Neil</span>.</p>
 <p>My band is called <span itemprop="band">Four Parts Water</span>.</p>
 <p>I am <span itemprop="nationality">British</span>.</p>
</div>

When a string value is a URLs, it is expressed using the a element and its href attribute, the img element and its src attribute, or other elements that link to or embed external resources.

<div itemscope>
 <img itemprop="image" src="google-logo.png" alt="Google">
</div>

When a string value is in some machine-readable format unsuitable for human consumption, it is expressed using the value attribute of the data element, with the human-readable version given in the element's contents.

<h1 itemscope>
 <data itemprop="product-id" value="9678AOU879">The Instigator 2000</data>
</h1>

For date- and time-related data, the time element and its datetime attribute can be used instead.

<div itemscope>
 I was born on <time itemprop="birthday" datetime="2009-05-10">May 10th 2009</time>.
</div>

Properties can also themselves be groups of name-value pairs, by putting the itemscope attribute on the element that declares the property.

Items that are not part of others are called top-level microdata items.

<div itemscope>
 <p>Name: <span itemprop="name">Amanda</span></p>
 <p>Band: <span itemprop="band" itemscope> <span itemprop="name">Jazz Band</span> (<span itemprop="size">12</span> players)</span></p>
</div>

Properties that are not descendants of the element with the itemscope attribute can be associated with the item using the itemref attribute. This attribute takes a list of IDs of elements to crawl in addition to crawling the children of the element with the itemscope attribute.

<div itemscope id="amanda" itemref="a b"></div>
<p id="a">Name: <span itemprop="name">Amanda</span></p>
<div id="b" itemprop="band" itemscope itemref="c"></div>
<div id="c">
 <p>Band: <span itemprop="name">Jazz Band</span></p>
 <p>Size: <span itemprop="size">12</span> players</p>
</div>

An item can have multiple properties with the same name and different values.

<div itemscope>
 <p>Flavors in my favorite ice cream:</p>
 <ul>
  <li itemprop="flavor">Lemon sorbet</li>
  <li itemprop="flavor">Apricot sorbet</li>
 </ul>
</div>

An element introducing a property can also introduce multiple properties at once, to avoid duplication when some of the properties have the same value.

<div itemscope>
 <span itemprop="favorite-color favorite-fruit">orange</span>
</div>

It's important to note that there is no relationship between the microdata and the content of the document where the microdata is marked up.

<figure>
 <img src="castle.jpeg">
 <figcaption><span itemscope><span itemprop="name">The Castle</span></span> (1986)</figcaption>
</figure>

<span itemscope><meta itemprop="name" content="The Castle"></span>
<figure>
 <img src="castle.jpeg">
 <figcaption>The Castle (1986)</figcaption>
</figure>

4.3 Typed items

This section is non-normative.

The examples in the previous section show how information could be marked up on a page that doesn't expect its microdata to be re-used. Microdata is most useful, though, when it is used in contexts where other authors and readers are able to cooperate to make new uses of the markup.

For this purpose, it is necessary to give each item a type, such as "http://example.com/person", or "http://example.org/cat", or "http://band.example.net/". Types are identified as URLs.

The type for an item is given as the value of an itemtype attribute on the same element as the itemscope attribute.

<section itemscope itemtype="http://example.org/animals#cat">
 <h1 itemprop="name">Hedral</h1>
 <p itemprop="desc">Hedral is a male american domestic
 shorthair, with a fluffy black fur with white paws and belly.</p>
 <img itemprop="img" src="hedral.jpeg" alt="" title="Hedral, age 18 months">
</section>

The type gives the context for the properties, thus selecting a vocabulary: a property named "class" given for an item with the type "http://census.example/person" might refer to the economic class of an individual, while a property named "class" given for an item with the type "http://example.com/school/teacher" might refer to the classroom a teacher has been assigned. Several types can share a vocabulary. For example, the types "http://example.org/people/teacher" and "http://example.org/people/engineer" could be defined to use the same vocabulary (though maybe some properties would not be especially useful in both cases, e.g. maybe the "http://example.org/people/engineer" type might not typically be used with the "classroom" property). Multiple types defined to use the same vocabulary can be given for a single item by listing the URLs as a space-separated list in the attribute' value. An item cannot be given two types if they do not use the same vocabulary, however.

4.4 Global identifiers for items

This section is non-normative.

Sometimes, an item gives information about a topic that has a global identifier. For example, books can be identified by their ISBN number.

Vocabularies (as identified by the itemtype attribute) can be designed such that items get associated with their global identifier in an unambiguous way by expressing the global identifiers as URLs given in an itemid attribute.

The exact meaning of the URLs given in itemid attributes depends on the vocabulary used.

<dl itemscope
    itemtype="http://vocab.example.net/book"
    itemid="urn:isbn:0-330-34032-8">
 <dt>Title
 <dd itemprop="title">The Reality Dysfunction
 <dt>Author
 <dd itemprop="author">Peter F. Hamilton
 <dt>Publication date
 <dd><time itemprop="pubdate" datetime="1996-01-26">26 January 1996</time>
</dl>

4.5 Selecting names when defining vocabularies

This section is non-normative.

Using microdata means using a vocabulary. For some purposes, an ad-hoc vocabulary is adequate. For others, a vocabulary will need to be designed. Where possible, authors are encouraged to re-use existing vocabularies, as this makes content re-use easier.

When designing new vocabularies, identifiers can be created either using URLs, or, for properties, as plain words (with no dots or colons). For URLs, conflicts with other vocabularies can be avoided by only using identifiers that correspond to pages that the author has control over.

Properties whose names are just plain words can only be used within the context of the types for which they are intended; properties named using URLs can be reused in items of any type. If an item has no type, and is not part of another item, then if its properties have names that are just plain words, they are not intended to be globally unique, and are instead only intended for limited use. Generally speaking, authors are encouraged to use either properties with globally unique names (URLs) or ensure that their items are typed.

<section itemscope itemtype="http://example.org/animals#cat">
 <h1 itemprop="name http://example.com/fn">Hedral</h1>
 <p itemprop="desc">Hedral is a male american domestic
 shorthair, with a fluffy <span
 itemprop="http://example.com/color">black</span> fur with <span
 itemprop="http://example.com/color">white</span> paws and belly.</p>
 <img itemprop="img" src="hedral.jpeg" alt="" title="Hedral, age 18 months">
</section>

4.6 Using the microdata DOM API

This section is non-normative.

The microdata becomes even more useful when scripts can use it to expose information to the user, for example offering it in a form that can be used by other applications.

The document.getItems(typeNames) method provides access to the top-level microdata items. It returns a NodeList containing the items with the specified types, or all types if no argument is specified.

Each item is represented in the DOM by the element on which the relevant itemscope attribute is found. These elements have their element.itemScope IDL attribute set to true.

The type(s) of items can be obtained using the element.itemType IDL attribute on the element with the itemscope attribute.

var cats = document.getItems("http://example.com/feline");

Once an element representing an item has been obtained, its properties can be extracted using the properties IDL attribute. This attribute returns an HTMLPropertiesCollection, which can be enumerated to go through each element that adds one or more properties to the item. It can also be indexed by name, which will return an object with a list of the elements that add properties with that name.

Each element that adds a property also has a itemValue IDL attribute that returns its value.

var user = document.getItems('http://example.net/user')[0];
alert('Hello ' + user.properties['name'][0].itemValue + '!');

The HTMLPropertiesCollection object, when indexed by name in this way, actually returns a PropertyNodeList object with all the matching properties. The PropertyNodeList object can be used to obtain all the values at once using its getValues method, which returns an array of all the values.

var cat = document.getItems('http://example.org/animals#cat')[0];
var colors = cat.properties['http://example.com/color'].getValues();
var result;
if (colors.length == 0) {
  result = 'Color unknown.';
} else if (colors.length == 1) {
  result = 'Color: ' + colors[0];
} else {
  result = 'Colors:';
  for (var i = 0; i < colors.length; i += 1)
    result += ' ' + colors[i];
}

It's also possible to get a list of all the property names using the object's names IDL attribute.

var outer = document.createElement('ul');
var items = document.getItems();
for (var item = 0; item < items.length; item += 1) {
  var itemLi = document.createElement('li');
  var inner = document.createElement('ul');
  for (var name = 0; name < items[item].properties.names.length; name += 1) {
    var propLi = document.createElement('li');
    propLi.appendChild(document.createTextNode(items[item].properties.names[name]));
    inner.appendChild(propLi);
  }
  itemLi.appendChild(inner);
  outer.appendChild(itemLi);
}
document.body.appendChild(outer);

<section itemscope itemtype="http://example.org/animals#cat">
 <h1 itemprop="name http://example.com/fn">Hedral</h1>
 <p itemprop="desc">Hedral is a male american domestic
 shorthair, with a fluffy <span
 itemprop="http://example.com/color">black</span> fur with <span
 itemprop="http://example.com/color">white</span> paws and belly.</p>
 <img itemprop="img" src="hedral.jpeg" alt="" title="Hedral, age 18 months">
</section>

5 Encoding microdata

The following attributes are added as global attributes to HTML elements:

• itemid
• itemprop
• itemref
• itemscope
• itemtype

5.1 The microdata model

The microdata model consists of groups of name-value pairs known as items.

Each group is known as an item. Each item can have item types, a global identifier (if the vocabulary specified by the item types support global identifiers for items), and a list of name-value pairs. Each name in the name-value pair is known as a property, and each property has one or more values. Each value is either a string or itself a group of name-value pairs (an item). The names are unordered relative to each other, but if a particular name has multiple values, they do have a relative order.

An item is said to be a typed item when either it has an item type, or it is the value of a property of a typed item. The relevant types for a typed item is the item's item types, if it has one, or else is the relevant types of the item for which it is a property's value.

5.2 Items

Every HTML element may have an itemscope attribute specified. The itemscope attribute is a boolean attribute.

An element with the itemscope attribute specified creates a new item, a group of name-value pairs.

Elements with an itemscope attribute may have an itemtype attribute specified, to give the item types of the item.

The itemtype attribute, if specified, must have a value that is an unordered set of unique space-separated tokens that are case-sensitive, each of which is a valid URL that is an absolute URL, and all of which are defined to use the same vocabulary. The attribute's value must have at least one token.

The item types of an item are the tokens obtained by splitting the element's itemtype attribute's value on spaces. If the itemtype attribute is missing or parsing it in this way finds no tokens, the item is said to have no item types.

The item types must all be types defined in applicable specifications and must all be defined to use the same vocabulary.

The itemtype attribute must not be specified on elements that do not have an itemscope attribute specified.

Elements with an itemscope attribute and an itemtype attribute that references a vocabulary that is defined to support global identifiers for items may also have an itemid attribute specified, to give a global identifier for the item, so that it can be related to other items on pages elsewhere on the Web.

The itemid attribute, if specified, must have a value that is a valid URL potentially surrounded by spaces.

The global identifier of an item is the value of its element's itemid attribute, if it has one, resolved relative to the element on which the attribute is specified. If the itemid attribute is missing or if resolving it fails, it is said to have no global identifier.

The itemid attribute must not be specified on elements that do not have both an itemscope attribute and an itemtype attribute specified, and must not be specified on elements with an itemscope attribute whose itemtype attribute specifies a vocabulary that does not support global identifiers for items, as defined by that vocabulary's specification.

The exact meaning of a global identifier is determined by the vocabulary's specification. It is up to such specifications to define whether multiple items with the same global identifier (whether on the same page or on different pages) are allowed to exist, and what the processing rules for that vocabulary are with respect to handling the case of multiple items with the same ID.

Elements with an itemscope attribute may have an itemref attribute specified, to give a list of additional elements to crawl to find the name-value pairs of the item.

The itemref attribute, if specified, must have a value that is an unordered set of unique space-separated tokens that are case-sensitive, consisting of IDs of elements in the same home subtree.

The itemref attribute must not be specified on elements that do not have an itemscope attribute specified.

The itemref attribute is not part of the microdata data model. It is merely a syntactic construct to aid authors in adding annotations to pages where the data to be annotated does not follow a convenient tree structure. For example, it allows authors to mark up data in a table so that each column defines a separate item, while keeping the properties in the cells.

<dl itemscope itemtype="http://md.example.com/loco 
                        http://md.example.com/lighting">
 <dt>Name:
 <dd itemprop="name">Tank Locomotive (DB 80)
 <dt>Product code:
 <dd itemprop="product-code">33041
 <dt>Scale:
 <dd itemprop="scale">HO
 <dt>Digital:
 <dd itemprop="digital">Delta
</dl>

<dl itemscope itemtype="http://md.example.com/track
                       http://md.example.com/lighting">    
 <dt>Name:
 <dd itemprop="name">Turnout Lantern Kit
 <dt>Product code:
 <dd itemprop="product-code">74470
 <dt>Purpose:
 <dd>For retrofitting 2 <span itemprop="track-type">C</span> Track 
 turnouts. <meta itemprop="scale" content="HO">
</dl>

<dl itemscope itemtype="http://md.example.com/passengers">
 <dt>Name:
 <dd itemprop="name">Express Train Passenger Car (DB Am 203)
 <dt>Product code:
 <dd itemprop="product-code">8710
 <dt>Scale:
 <dd itemprop="scale">Z
</dl>

5.3 Names: the itemprop attribute

Every HTML element may have an itemprop attribute specified, if doing so adds one or more properties to one or more items (as defined below).

The itemprop attribute, if specified, must have a value that is an unordered set of unique space-separated tokens that are case-sensitive, representing the names of the name-value pairs that it adds. The attribute's value must have at least one token.

Each token must be either:

• A valid URL that is an absolute URL, or
• If the item is a typed item: a defined property name allowed in this situation according to the specification that defines the relevant types for the item, or
• If the item is not a typed item: a string that contains no "." (U+002E) characters and no ":" (U+003A) characters.

Specifications that introduce defined property names that are not absolute URLs must ensure all such property names contain no "." (U+002E) characters, no ":" (U+003A) characters, and no space characters.

When an element with an itemprop attribute adds a property to multiple items, the requirement above regarding the tokens applies for each item individually.

The property names of an element are the tokens that the element's itemprop attribute is found to contain when its value is split on spaces, with the order preserved but with duplicates removed (leaving only the first occurrence of each name).

Within an item, the properties are unordered with respect to each other, except for properties with the same name, which are ordered in the order they are given by the algorithm that defines the properties of an item.

<div itemscope>
 <p itemprop="a">1</p>
 <p itemprop="a">2</p>
 <p itemprop="b">test</p>
</div>

<div itemscope>
 <p itemprop="b">test</p>
 <p itemprop="a">1</p>
 <p itemprop="a">2</p>
</div>

<div itemscope>
 <p itemprop="a">1</p>
 <p itemprop="b">test</p>
 <p itemprop="a">2</p>
</div>

<div id="x">
 <p itemprop="a">1</p>
</div>
<div itemscope itemref="x">
 <p itemprop="b">test</p>
 <p itemprop="a">2</p>
</div>

5.4 Values

The property value of a name-value pair added by an element with an itemprop attribute is as given for the first matching case in the following list:

If the element also has an itemscope attribute

The value is the item created by the element.

If the element is a meta element

The value is the value of the element's content attribute, if any, or the empty string if there is no such attribute.

If the element is an audio, embed, iframe, img, source, track, or video element

The value is the absolute URL that results from resolving the value of the element's src attribute relative to the element at the time the attribute is set, or the empty string if there is no such attribute or if resolving it results in an error.

If the element is an a, area, or link element

The value is the absolute URL that results from resolving the value of the element's href attribute relative to the element at the time the attribute is set, or the empty string if there is no such attribute or if resolving it results in an error.

If the element is an object element

The value is the absolute URL that results from resolving the value of the element's data attribute relative to the element at the time the attribute is set, or the empty string if there is no such attribute or if resolving it results in an error.

If the element is a data element

The value is the value of the element's value attribute, if it has one, or the empty string otherwise.

If the element is a time element

The value is the element's datetime value.

Otherwise

The value is the element's textContent.

The URL property elements are the a, area, audio, embed, iframe, img, link, object, source, track, and video elements.

If a property's value, as defined by the property's definition, is an absolute URL, the property must be specified using a URL property element.

These requirements do not apply just because a property value happens to match the syntax for a URL. They only apply if the property is explicitly defined as taking such a value.

For example, a book about the first moon landing could be called "mission:moon". A "title" property from a vocabulary that defines a title as being a string would not expect the title to be given in an a element, even though it looks like a URL. On the other hand, if there was a (rather narrowly scoped!) vocabulary for "books whose titles look like URLs" which had a "title" property defined to take a URL, then the property would expect the title to be given in an a element (or one of the other URL property elements), because of the requirement above.

<!DOCTYPE HTML>
<html>
 <head>
  <title>Photo gallery</title>
 </head>
 <body>
  <h1>My photos</h1>
  <figure itemscope itemtype="http://n.whatwg.org/work" itemref="licenses">
   <img itemprop="work" src="images/house.jpeg" alt="A white house, boarded up, sits in a forest.">
   <figcaption itemprop="title">The house I found.</figcaption>
  </figure>
  <figure itemscope itemtype="http://n.whatwg.org/work" itemref="licenses">
   <img itemprop="work" src="images/mailbox.jpeg" alt="Outside the house is a mailbox. It has a leaflet inside.">
   <figcaption itemprop="title">The mailbox.</figcaption>
  </figure>
  <footer>
   <p id="licenses">All images licensed under the <a itemprop="license"
   href="http://www.opensource.org/licenses/mit-license.php">MIT
   license</a>.</p>
  </footer>
 </body>
</html>

5.6 Microdata and other namespaces

Currently, the itemscope, itemprop, and other microdata attributes are only defined for HTML elements. This means that attributes with the literal names "itemscope", "itemprop", etc, do not cause microdata processing to occur on elements in other namespaces, such as SVG.

<p itemscope></p> <!-- this is an item (with no properties and no type) -->
<svg itemscope></svg> <!-- this is not, it's just an svg element with an invalid unknown attribute -->

6 Microdata DOM API

partial interface Document { 
  NodeList getItems(optional DOMString typeNames); // microdata
};

partial interface HTMLElement {
  // microdata 
           attribute boolean itemScope;
  [PutForwards=value] readonly attribute DOMSettableTokenList itemType;
           attribute DOMString itemId;
  [PutForwards=value] readonly attribute DOMSettableTokenList itemRef;
  [PutForwards=value] readonly attribute DOMSettableTokenList itemProp;
  readonly attribute HTMLPropertiesCollection properties;
           attribute any itemValue;
};

document . getItems( [ types ] )

Returns a NodeList of the elements in the Document that create items, that are not part of other items, and that are of the types given in the argument, if any are listed.

The types argument is interpreted as a space-separated list of types.

element . properties

If the element has an itemscope attribute, returns an HTMLPropertiesCollection object with all the element's properties. Otherwise, an empty HTMLPropertiesCollection object.

element . itemValue [ = value ]

Returns the element's value.

Can be set, to change the element's value. Setting the value when the element has no itemprop attribute or when the element's value is an item throws an InvalidAccessError exception.

if (element.itemProp.contains('color'))
  count += 1;

for (var index = 0; index < element.itemRef.length; index += 1)
  process(document.getElementById(element.itemRef[index]));

6.1 HTMLPropertiesCollection

The HTMLPropertiesCollection interface is used for collections of elements that add name-value pairs to a particular item in the microdata model.

interface HTMLPropertiesCollection : HTMLCollection {
  // inherits length and item()
  getter PropertyNodeList? namedItem(DOMString name); // overrides inherited namedItem()
  readonly attribute DOMString[] names;
};

typedef sequence<any> PropertyValueArray;

interface PropertyNodeList : NodeList {
  PropertyValueArray getValues();
};

collection . length

Returns the number of elements in the collection.

element = collection . item(index)

collection[index]

Returns the element with index index from the collection. The items are sorted in tree order.

propertyNodeList = collection . namedItem(name)

element = collection . item(name)

Returns a PropertyNodeList object containing any elements that add a property named name.

collection[name]

Returns a PropertyNodeList object containing any elements that add a property named name. The name index has to be one of the values listed in the names list.

collection . names

Returns an array with the property names of the elements in the collection.

propertyNodeList . getValues()

Returns an array of the various values that the relevant elements have.

7 Other changes to HTML5

7.1 Content models

If the itemprop attribute is present on link or meta, they are flow content and phrasing content. The link and meta elements may be used where phrasing content is expected if the itemprop attribute is present.

If a link element has an itemprop attribute, the rel attribute may be omitted.

If a meta element has an itemprop attribute, the name, http-equiv, and charset attributes must be omitted, and the content attribute must be present.

If the itemprop is specified on an a or area element, then the href attribute must also be specified.

If the itemprop is specified on an iframe element, then the data attribute must also be specified.

If the itemprop is specified on an embed element, then the data attribute must also be specified.

If the itemprop is specified on an object element, then the data attribute must also be specified.

If the itemprop is specified on a media element, then the src attribute must also be specified.

9 IANA considerations

application/microdata+json

This registration is for community review and will be submitted to the IESG for review, approval, and registration with IANA.

Type name:

application

Subtype name:

microdata+json

Required parameters:

Same as for application/json [JSON]

Optional parameters:

Same as for application/json [JSON]

Encoding considerations:

8bit (always UTF-8)

Security considerations:

Same as for application/json [JSON]

Interoperability considerations:

Same as for application/json [JSON]

Published specification:

Labeling a resource with the application/microdata+json type asserts that the resource is a JSON text that consists of an object with a single entry called "items" consisting of an array of entries, each of which consists of an object with an entry called "id" whose value is a string, an entry called "type" whose value is another string, and an entry called "properties" whose value is an object whose entries each have a value consisting of an array of either objects or strings, the objects being of the same form as the objects in the aforementioned "items" entry. Thus, the relevant specifications are the JSON specification and this specification. [JSON]

Applications that use this media type:

Applications that transfer data intended for use with HTML's microdata feature, especially in the context of drag-and-drop, are the primary application class for this type.

Additional information:

Magic number(s):

Same as for application/json [JSON]

File extension(s):

Same as for application/json [JSON]

Macintosh file type code(s):

Same as for application/json [JSON]

Person & email address to contact for further information:

Ian Hickson <[email protected]>

Intended usage:

Common

Restrictions on usage:

No restrictions apply.

Author:

Ian Hickson <[email protected]>

Change controller:

W3C

Fragment identifiers used with application/microdata+json resources have the same semantics as when used with application/json (namely, at the time of writing, no semantics at all). [JSON]

References

All references are normative unless marked "Non-normative".

[ABNF]

Augmented BNF for Syntax Specifications: ABNF, D. Crocker, P. Overell. IETF.

[ABOUT]

The 'about' URI scheme, L. Hunt, M. Yevstifeyev. IETF. Work in progress.

[AES128CTR]

Advanced Encryption Standard (AES). NIST.

[AGIF]

(Non-normative) GIF Application Extension: NETSCAPE2.0. R. Frazier.

[APNG]

(Non-normative) APNG Specification. S. Parmenter, V. Vukicevic, A. Smith. Mozilla.

[ARIA]

Accessible Rich Internet Applications (WAI-ARIA), J. Craig, M. Cooper, L. Pappas, R. Schwerdtfeger, L. Seeman. W3C.

[ARIAIMPL]

WAI-ARIA 1.0 User Agent Implementation Guide, A. Snow-Weaver, M. Cooper. W3C.

[ATAG]

(Non-normative) Authoring Tool Accessibility Guidelines (ATAG) 2.0, J. Richards, J. Spellman, J. Treviranus. W3C.

[ATOM]

(Non-normative) The Atom Syndication Format, M. Nottingham, R. Sayre. IETF.

[BCP47]

Tags for Identifying Languages; Matching of Language Tags, A. Phillips, M. Davis. IETF.

[BECSS]

Behavioral Extensions to CSS, I. Hickson. W3C.

[BEZIER]

Courbes à poles, P. de Casteljau. INPI, 1959.

[BIDI]

UAX #9: Unicode Bidirectional Algorithm, M. Davis. Unicode Consortium.

[BIG5]

(Non-normative) Chinese Coded Character Set in Computer. Institute for Information Industry, March 1984.

[BOCU1]

(Non-normative) UTN #6: BOCU-1: MIME-Compatible Unicode Compression, M. Scherer, M. Davis. Unicode Consortium.

[CESU8]

(Non-normative) UTR #26: Compatibility Encoding Scheme For UTF-16: 8-BIT (CESU-8), T. Phipps. Unicode Consortium.

[CHARMOD]

(Non-normative) Character Model for the World Wide Web 1.0: Fundamentals, M. Dürst, F. Yergeau, R. Ishida, M. Wolf, T. Texin. W3C.

[CLDR]

Unicode Common Locale Data Repository. Unicode.

[COMPUTABLE]

(Non-normative) On computable numbers, with an application to the Entscheidungsproblem, A. Turing. In Proceedings of the London Mathematical Society, series 2, volume 42, pages 230-265. London Mathematical Society, 1937.

[COOKIES]

HTTP State Management Mechanism, A. Barth. IETF.

[CORS]

Cross-Origin Resource Sharing, A. van Kesteren. W3C.

[CP50220]

CP50220, Y. Naruse. IANA.

[CP51932]

CP51932, Y. Naruse. IANA.

[CSP]

(Non-normative) Content Security Policy, B. Sterne, A. Barth. W3C.

[CSS]

Cascading Style Sheets Level 2 Revision 1, B. Bos, T. Çelik, I. Hickson, H. Lie. W3C.

[CSSANIMATIONS]

(Non-normative) CSS Animations, D. Jackson, D. Hyatt, C. Marrin, S. Galineau, L. Baron. W3C.

[CSSATTR]

CSS Styling Attribute Syntax, T. Çelik, E. Etemad. W3C.

[CSSCOLOR]

CSS Color Module Level 3, T. Çelik, C. Lilley, L. Baron. W3C.

[CSSFONTS]

CSS Fonts Module Level 3, J. Daggett. W3C.

[CSSIMAGES]

CSS Image Values and Replaced Content Module Level 3, E. Etemad, T. Atkins. W3C.

[CSSOM]

Cascading Style Sheets Object Model (CSSOM), A. van Kesteren. W3C.

[CSSOMVIEW]

CSSOM View Module, A. van Kesteren. W3C.

[CSSRUBY]

CSS3 Ruby Module, R. Ishida. W3C.

[CSSTRANSITIONS]

(Non-normative) CSS Transitions, D. Jackson, D. Hyatt, C. Marrin, L. Baron. W3C.

[CSSUI]

CSS3 Basic User Interface Module, T. Çelik. W3C.

[CSSVALUES]

CSS3 Values and Units, H. Lie, T. Atkins, E. Etemad. W3C.

[DASH]

Dynamic adaptive streaming over HTTP (DASH). ISO.

[DOMCORE]

Web DOM Core, A. van Kesteren. W3C.

[DOMEVENTS]

Document Object Model (DOM) Level 3 Events Specification, T. Leithead, J. Rossi, D. Schepers, B. Höhrmann, P. Le Hégaret, T. Pixley. W3C.

[DOMPARSING]

DOM Parsing and Serialization, T. Leithead. Work in Progress. W3C.

[DOT]

(Non-normative) The DOT Language. Graphviz.

[E163]

Recommendation E.163 — Numbering Plan for The International Telephone Service, CCITT Blue Book, Fascicle II.2, pp. 128-134, November 1988.

[ECMA262]

ECMAScript Language Specification. ECMA.

[ECMA357]

(Non-normative) ECMAScript for XML (E4X) Specification. ECMA.

[EDITING]

HTML Editing APIs, A. Gregor.

[EUCKR]

Hangul Unix Environment. Korea Industrial Standards Association. Ref. No. KS C 5861-1992.

[EUCJP]

Definition and Notes of Japanese EUC. UI-OSF-USLP. In English in the abridged translation of the UI-OSF Application Platform Profile for Japanese Environment, Appendix C.

[EVENTSOURCE]

Server-Sent Events, I. Hickson. W3C.

[FILEAPI]

File API, A. Ranganathan. W3C.

[FILESYSTEMAPI]

File API: Directories and System, E. Uhrhane. W3C.

[FULLSCREEN]

Fullscreen, A. van Kesteren, T. Çelik.

[GBK]

Chinese Internal Code Specification. Chinese IT Standardization Technical Committee.

[GIF]

(Non-normative) Graphics Interchange Format. CompuServe.

[GRAPHICS]

(Non-normative) Computer Graphics: Principles and Practice in C, Second Edition, J. Foley, A. van Dam, S. Feiner, J. Hughes. Addison-Wesley. ISBN 0-201-84840-6.

[GREGORIAN]

(Non-normative) Inter Gravissimas, A. Lilius, C. Clavius. Gregory XIII Papal Bull, February 1582.

[HATOM]

(Non-normative) hAtom, D Janes. Microformats.

[HMAC]

The Keyed-Hash Message Authentication Code (HMAC). NIST.

[HPAAIG]

HTML to Platform Accessibility APIs Implementation Guide. W3C.

[HTML4]

(Non-normative) HTML 4.01 Specification, D. Raggett, A. Le Hors, I. Jacobs. W3C.

[HTML]

HTML, I. Hickson. WHATWG.

[HTML5]

HTML5, I. Hickson. W3C.

[HTMLALTTECHS]

(Non-normative) HTML5: Techniques for providing useful text alternatives, S. Faulkner. W3C.

[HTMLDIFF]

(Non-normative) HTML5 differences from HTML4, A. van Kesteren. W3C.

[HTTP]

Hypertext Transfer Protocol — HTTP/1.1, R. Fielding, J. Gettys, J. Mogul, H. Frystyk, L. Masinter, P. Leach, T. Berners-Lee. IETF.

[HTTPS]

(Non-normative) HTTP Over TLS, E. Rescorla. IETF.

[IANACHARSET]

Character Sets. IANA.

[IANALINKTYPE]

Link Relations. IANA.

[IANAPERMHEADERS]

Permanent Message Header Field Names. IANA.

[ICE]

Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal for Offer/Answer Protocols, J. Rosenberg. IETF.

[IEEE754]

IEEE Standard for Floating-Point Arithmetic (IEEE 754). IEEE. ISBN 978-0-7381-5753-5.

[ISO8601]

(Non-normative) ISO8601: Data elements and interchange formats — Information interchange — Representation of dates and times. ISO.

[ISO885911]

ISO-8859-11: Information technology — 8-bit single-byte coded graphic character sets — Part 11: Latin/Thai alphabet. ISO.

[JLREQ]

Requirements for Japanese Text Layout. W3C.

[JPEG]

JPEG File Interchange Format, E. Hamilton.

[JSON]

The application/json Media Type for JavaScript Object Notation (JSON), D. Crockford. IETF.

[JSURL]

The 'javascript' resource identifier scheme, B. Höhrmann. IETF. Work in progress.

[MAILTO]

(Non-normative) The 'mailto' URI scheme, M. Duerst, L. Masinter, J. Zawinski. IETF.

[MATHML]

Mathematical Markup Language (MathML), D. Carlisle, P. Ion, R. Miner, N. Poppelier. W3C.

[MEDIAFRAG]

Media Fragments URI, R. Troncy, E. Mannens, S. Pfeiffer, D. Van Deursen. W3C.

[MFREL]

Microformats Wiki: existing rel values. Microformats.

[MIMESNIFF]

MIME Sniffing, A. Barth, I. Hickson. WHATWG.

[MNG]

MNG (Multiple-image Network Graphics) Format. G. Randers-Pehrson.

[MPEG2]

ISO/IEC 13818-1: Information technology — Generic coding of moving pictures and associated audio information: Systems. ISO/IEC.

[MPEG4]

ISO/IEC 14496-12: ISO base media file format. ISO/IEC.

[MQ]

Media Queries, H. Lie, T. Çelik, D. Glazman, A. van Kesteren. W3C.

[NPAPI]

(Non-normative) Gecko Plugin API Reference. Mozilla.

[NPN]

Transport Layer Security (TLS) Next Protocol Negotiation Extension, A. Langley. IETF. Work in progress.

[OGGSKELETONHEADERS]

SkeletonHeaders. Xiph.Org.

[OPENSEARCH]

Autodiscovery in HTML/XHTML. In OpenSearch 1.1 Draft 4, Section 4.6.2. OpenSearch.org.

[ORIGIN]

The Web Origin Concept, A. Barth. IETF.

[PAGEVIS]

(Non-normative) Page Visibility, J. Mann, A. Jain. W3C.

[PDF]

(Non-normative) Document management — Portable document format — Part 1: PDF. ISO.

[PINGBACK]

Pingback 1.0, S. Langridge, I. Hickson.

[PNG]

Portable Network Graphics (PNG) Specification, D. Duce. W3C.

[POLYGLOT]

(Non-normative) Polyglot Markup: HTML-Compatible XHTML Documents, E. Graff. W3C.

[PORTERDUFF]

Compositing Digital Images, T. Porter, T. Duff. In Computer graphics, volume 18, number 3, pp. 253-259. ACM Press, July 1984.

[PPUTF8]

(Non-normative) The Properties and Promises of UTF-8, M. Dürst. University of Zürich. In Proceedings of the 11th International Unicode Conference.

[PROGRESS]

Progress Events, A. van Kesteren. W3C.

[PSL]

Public Suffix List. Mozilla Foundation.

[RFC1034]

Domain Names - Concepts and Facilities, P. Mockapetris. IETF, November 1987.

[RFC1321]

The MD5 Message-Digest Algorithm, R. Rivest. IETF.

[RFC1345]

Character Mnemonics and Character Sets, K. Simonsen. IETF.

[RFC1468]

Japanese Character Encoding for Internet Messages, J. Murai, M. Crispin, E. van der Poel. IETF.

[RFC1494]

(Non-normative) Equivalences between 1988 X.400 and RFC-822 Message Bodies, H. Alvestrand, S. Thompson. IETF.

[RFC1554]

ISO-2022-JP-2: Multilingual Extension of ISO-2022-JP, M. Ohta, K. Handa. IETF.

[RFC1557]

Korean Character Encoding for Internet Messages, U. Choi, K. Chon, H. Park. IETF.

[RFC1842]

ASCII Printable Characters-Based Chinese Character Encoding for Internet Messages, Y. Wei, Y. Zhang, J. Li, J. Ding, Y. Jiang. IETF.

[RFC1922]

Chinese Character Encoding for Internet Messages, HF. Zhu, DY. Hu, ZG. Wang, TC. Kao, WCH. Chang, M. Crispin. IETF.

[RFC2045]

Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies, N. Freed, N. Borenstein. IETF.

[RFC2046]

Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types, N. Freed, N. Borenstein. IETF.

[RFC2119]

Key words for use in RFCs to Indicate Requirement Levels, S. Bradner. IETF.

[RFC2237]

Japanese Character Encoding for Internet Messages, K. Tamaru. IETF.

[RFC2246]

The TLS Protocol Version 1.0, T. Dierks, C. Allen. IETF.

[RFC2313]

PKCS #1: RSA Encryption, B. Kaliski. IETF.

[RFC2318]

The text/css Media Type, H. Lie, B. Bos, C. Lilley. IETF.

[RFC2388]

Returning Values from Forms: multipart/form-data, L. Masinter. IETF.

[RFC2397]

The "data" URL scheme, L. Masinter. IETF.

[RFC2445]

Internet Calendaring and Scheduling Core Object Specification (iCalendar), F. Dawson, D. Stenerson. IETF.

[RFC2483]

URI Resolution Services Necessary for URN Resolution, M. Mealling, R. Daniel. IETF.

[RFC2781]

UTF-16, an encoding of ISO 10646, P. Hoffman, F. Yergeau. IETF.

[RFC3676]

The Text/Plain Format and DelSp Parameters, R. Gellens. IETF.

[RFC2806]

(Non-normative) URLs for Telephone Calls, A. Vaha-Sipila. IETF.

[RFC3023]

XML Media Types, M. Murata, S. St. Laurent, D. Kohn. IETF.

[RFC3279]

Algorithms and Identifiers for the Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile, W. Polk, R. Housley, L. Bassham. IETF.

[RFC3490]

Internationalizing Domain Names in Applications (IDNA), P. Faltstrom, P. Hoffman, A. Costello. IETF.

[RFC3629]

UTF-8, a transformation format of ISO 10646, F. Yergeau. IETF.

[RFC3864]

Registration Procedures for Message Header Fields, G. Klyne, M. Nottingham, J. Mogul. IETF.

[RFC3986]

Uniform Resource Identifier (URI): Generic Syntax, T. Berners-Lee, R. Fielding, L. Masinter. IETF.

[RFC3987]

Internationalized Resource Identifiers (IRIs), M. Dürst, M. Suignard. IETF.

[RFC4281]

The Codecs Parameter for "Bucket" Media Types, R. Gellens, D. Singer, P. Frojdh. IETF.

[RFC4329]

(Non-normative) Scripting Media Types, B. Höhrmann. IETF.

[RFC4366]

Transport Layer Security (TLS) Extensions, S. Blake-Wilson, M. Nystrom, D. Hopwood, J. Mikkelsen, T. Wright. IETF.

[RFC4395]

Guidelines and Registration Procedures for New URI Schemes, T. Hansen, T. Hardie, L. Masinter. IETF.

[RFC4648]

The Base16, Base32, and Base64 Data Encodings, S. Josefsson. IETF.

[RFC4770]

vCard Extensions for Instant Messaging (IM), C. Jennings, J. Reschke. IETF.

[RFC5280]

Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile, D. Cooper, S. Santesson, S. Farrell, S. Boeyen, R. Housley, W. Polk. IETF.

[RFC5322]

Internet Message Format, P. Resnick. IETF.

[RFC5724]

URI Scheme for Global System for Mobile Communications (GSM) Short Message Service (SMS), E. Wilde, A. Vaha-Sipila. IETF.

[RFC6266]

Use of the Content-Disposition Header Field in the Hypertext Transfer Protocol (HTTP), J. Reschke. IETF.

[RFC6350]

vCard Format Specification, S. Perreault. IETF.

[SCSU]

(Non-normative) UTR #6: A Standard Compression Scheme For Unicode, M. Wolf, K. Whistler, C. Wicksteed, M. Davis, A. Freytag, M. Scherer. Unicode Consortium.

[SDP]

SDP: Session Description Protocol, M. Handley, V. Jacobson, C. Perkins. IETF.

[SDPLABEL]

The Session Description Protocol (SDP) Label Attribute, O. Levin, G. Camarillo. IETF.

[SDPOFFERANSWER]

An Offer/Answer Model with the Session Description Protocol (SDP), J. Rosenberg, H. Schulzrinne. IETF.

[SELECTORS]

Selectors, E. Etemad, T. Çelik, D. Glazman, I. Hickson, P. Linss, J. Williams. W3C.

[SHA1]

Secure Hash Standard. NIST.

[SHIFTJIS]

JIS X0208: 7-bit and 8-bit double byte coded KANJI sets for information interchange. Japanese Industrial Standards Committee.

[SRGB]

IEC 61966-2-1: Multimedia systems and equipment — Colour measurement and management — Part 2-1: Colour management — Default RGB colour space — sRGB. IEC.

[STUN]

Session Traversal Utilities for NAT (STUN), J. Rosenberg, R. Mahy, P. Matthews, D. Wing. IETF.

[SVG]

Scalable Vector Graphics (SVG) Tiny 1.2 Specification, O. Andersson, R. Berjon, E. Dahlström, A. Emmons, J. Ferraiolo, A. Grasso, V. Hardy, S. Hayman, D. Jackson, C. Lilley, C. McCormack, A. Neumann, C. Northway, A. Quint, N. Ramani, D. Schepers, A. Shellshear. W3C.

[TIS620]

UDC 681.3.04:003.62. Thai Industrial Standards Institute, Ministry of Industry, Royal Thai Government. ISBN 974-606-153-4.

[TURN]

Traversal Using Relays around NAT (TURN): Relay Extensions to Session Traversal Utilities for NAT (STUN), R. Mahy, P. Matthews, J. Rosenberg. IETF.

[TIMEZONES]

(Non-normative) Working with Time Zones, A. Phillips, N. Lindenberg, M. Davis, M.J. Dürst, F. Sasaki, R. Ishida. W3C.

[TYPEDARRAY]

Typed Array Specification, D. Herman, K. Russell. Khronos.

[UAAG]

(Non-normative) User Agent Accessibility Guidelines (UAAG) 2.0, J. Allan, K. Ford, J. Richards, J. Spellman. W3C.

[UNDO]

UndoManager and DOM Transaction, R. Niwa.

[UNICODE]

The Unicode Standard. Unicode Consortium.

[UNIVCHARDET]

(Non-normative) A composite approach to language/encoding detection, S. Li, K. Momoi. Netscape. In Proceedings of the 19th International Unicode Conference.

[UTF7]

UTF-7: A Mail-Safe Transformation Format of Unicode, D. Goldsmith, M. Davis. IETF.

[UTF8DET]

(Non-normative) Multilingual form encoding, M. Dürst. W3C.

[UTR36]

(Non-normative) UTR #36: Unicode Security Considerations, M. Davis, M. Suignard. Unicode Consortium.

[WCAG]

(Non-normative) Web Content Accessibility Guidelines (WCAG) 2.0, B. Caldwell, M. Cooper, L. Reid, G. Vanderheiden. W3C.

[WEBADDRESSES]

Web addresses in HTML5, D. Connolly, C. Sperberg-McQueen.

[WEBGL]

WebGL Specification, C. Marrin. Khronos Group.

[WEBIDL]

Web IDL, C. McCormack. W3C.

[WEBLINK]

Web Linking, M. Nottingham. IETF.

[WEBMCG]

WebM Container Guidelines. The WebM Project.

[WEBSOCKET]

The WebSocket API, I. Hickson. W3C.

[WEBSTORAGE]

Web Storage, I. Hickson. W3C.

[WEBVTT]

WebVTT, I. Hickson. W3C.

[WEBWORKERS]

Web Workers, I. Hickson. W3C.

[WHATWGBLOG]

The WHATWG Blog. WHATWG.

[WHATWGWIKI]

The WHATWG Wiki. WHATWG.

[WIN1252]

Windows 1252. Microsoft.

[WIN1254]

Windows 1254. Microsoft.

[WIN31J]

Windows Codepage 932. Microsoft.

[WIN874]

Windows 874. Microsoft.

[WIN949]

Windows Codepage 949. Microsoft.

[WSP]

The WebSocket protocol, I. Fette, A. Melnikov. IETF.

[X121]

Recommendation X.121 — International Numbering Plan for Public Data Networks, CCITT Blue Book, Fascicle VIII.3, pp. 317-332.

[X690]

Recommendation X.690 — Information Technology — ASN.1 Encoding Rules — Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER), and Distinguished Encoding Rules (DER). International Telecommunication Union.

[XFN]

XFN 1.1 profile, T. Çelik, M. Mullenweg, E. Meyer. GMPG.

[XHR]

XMLHttpRequest, A. van Kesteren. W3C.

[XHTML1]

XHTML(TM) 1.0 The Extensible HyperText Markup Language (Second Edition). W3C.

[XHTMLMOD]

Modularization of XHTML(TM), M. Altheim, F. Boumphrey, S. Dooley, S. McCarron, S. Schnitzenbaumer, T. Wugofski. W3C.

[XML]

Extensible Markup Language, T. Bray, J. Paoli, C. Sperberg-McQueen, E. Maler, F. Yergeau. W3C.

[XMLBASE]

XML Base, J. Marsh, R. Tobin. W3C.

[XMLNS]

Namespaces in XML, T. Bray, D. Hollander, A. Layman, R. Tobin. W3C.

[XPATH10]

XML Path Language (XPath) Version 1.0, J. Clark, S. DeRose. W3C.

[XSLT10]

(Non-normative) XSL Transformations (XSLT) Version 1.0, J. Clark. W3C.