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</div>
</div>
</header>
<hr>
<div id="configUI"></div>
<h2 class="no-num no-toc" id="contents">Table of contents</h2>
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<pre class="idl">
interface Screen { }; // CSSOM
interface URL { }; // URL API
interface Blob { }; // File API
interface File : Blob { }; // File API
interface FileList { }; // File API
interface WebGLRenderingContext { }; // WebGL
interface XMLDocument { }; // DOM
interface HTMLCollection { }; // DOM
interface DOMTokenList { }; // DOM
interface DOMSettableTokenList { attribute any value; }; // DOM
interface SVGMatrix { }; // SVG
// fake interfaces that map to JS object types:
interface ArrayBuffer { };
interface Int8Array { };
interface Uint8Array { };
interface Uint8ClampedArray { };
interface Int16Array { };
interface Uint16Array { };
interface Int32Array { };
interface Uint32Array { };
interface Float32Array { };
interface Float64Array { };
interface Uint8ClampedArray { };
</pre>
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<h2 id="introduction">Introduction</h2>
<div class="nodev">
<h3 id="abstract">Where does this specification fit?</h3>
<p>This specification defines a big part of the Web platform, in lots of detail. Its place in the
Web platform specification stack relative to other specifications can be best summed up as
follows:</p>
<p><img src="images/abstract.png" width="398" height="359" alt="It consists of everything else, above such core technologies as HTTP, URI/IRIs, DOM, XML, Unicode, and ECMAScript; below presentation-layer technologies like CSS and the NPAPI; and to the side of technologies like Geolocation, SVG, MathML, and XHR."></p>
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<h3 id="is-this-html5?">Is this HTML5?</h3>
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<p>In short: Yes.</p>
<p>In more length: The term "HTML5" is widely used as a buzzword to refer to modern Web
technologies, many of which (though by no means all) are developed at the WHATWG. This document is
one such; others are available from <a href="http://www.whatwg.org/specs/">the WHATWG
specification index</a>.</p>
<p class="note">Although we have asked them to stop doing so, the W3C also republishes some parts
of this specification as separate documents. There are numerous differences between this
specification and the W3C forks; some minor, some major. Unfortunately these are not currently
accurately documented anywhere, so there is no way to know which are intentional and which are
not.</p>
<h3>Background</h3>
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<p>HTML is the World Wide Web's core markup language. Originally, HTML was primarily designed as a
language for semantically describing scientific documents. Its general design, however, has
enabled it to be adapted, over the subsequent years, to describe a number of other types of
documents and even applications.</p>
<h3>Audience</h3>
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<p>This specification is intended for authors of documents and scripts that use the features
defined in this specification<span class="nodev">, implementors of tools that operate on pages that
use the features defined in this specification, and individuals wishing to establish the
correctness of documents or implementations with respect to the requirements of this
specification</span>.</p>
<p>This document is probably not suited to readers who do not already have at least a passing
familiarity with Web technologies, as in places it sacrifices clarity for precision, and brevity
for completeness. More approachable tutorials and authoring guides can provide a gentler
introduction to the topic.</p>
<p>In particular, familiarity with the basics of DOM is necessary for a complete understanding of
some of the more technical parts of this specification. An understanding of Web IDL, HTTP, XML,
Unicode, character encodings, JavaScript, and CSS will also be helpful in places but is not
essential.</p>
<h3>Scope</h3>
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<p>This specification is limited to providing a semantic-level markup language and associated
semantic-level scripting APIs for authoring accessible pages on the Web ranging from static
documents to dynamic applications.</p>
<p>The scope of this specification does not include providing mechanisms for media-specific
customization of presentation (although default rendering rules for Web browsers are included at
the end of this specification, and several mechanisms for hooking into CSS are provided as part of
the language).</p>
<p>The scope of this specification is not to describe an entire operating system. In particular,
hardware configuration software, image manipulation tools, and applications that users would be
expected to use with high-end workstations on a daily basis are out of scope. In terms of
applications, this specification is targeted specifically at applications that would be expected
to be used by users on an occasional basis, or regularly but from disparate locations, with low
CPU requirements. Examples of such applications include online purchasing systems, searching
systems, games (especially multiplayer online games), public telephone books or address books,