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<!DOCTYPE html><html lang="en-US"><head>
<meta charset="utf-8">
<title>HTML differences from HTML4</title>
<style>
.note { margin-left:2em; font-weight:bold; font-style:italic; color:green }
p.note::before { content:"Note: " }
dfn { font-style:normal; font-weight:bold }
code { color:orangered; font-size:14px }
h3 code { font-size:17px }
code :link, code :visited { color:inherit }
pre code { color:inherit }
pre strong { color:inherit; background:#ffa }
</style>
<link class="not-whatwg" href="http://www.w3.org/StyleSheets/TR/W3C-ED" rel="stylesheet">
</head>
<body>
<!--
Editor's checklist for stuff to fix for publication:
* Previous Versions links
* Changelog headings
-->
<div class="head">
<div class="not-whatwg">
<!--begin-logo-->
<p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="https://www.w3.org/Icons/w3c_home" width="72"></a></p>
<!--end-logo--></div>
<hgroup>
<h1>HTML differences from HTML4</h1>
<h2 class="no-num no-toc not-whatwg" id="w3c-doctype">Editor's Draft 2 May 2013</h2>
</hgroup>
<dl>
<dt>This Version:</dt>
<dd class="not-tr not-whatwg"><a href="http://dev.w3.org/html5/html4-differences/">http://dev.w3.org/html5/html4-differences/</a>
<dt>Participate:</dt>
<dd><a href="https://www.w3.org/Bugs/Public/enter_bug.cgi?product=HTML%20WG&component=HTML5%20differences%20from%20HTML4">file a bug</a>
(<a href="https://www.w3.org/Bugs/Public/buglist.cgi?product=HTML%20WG&component=HTML5%20differences%20from%20HTML4&resolution=---">open bugs</a>)
<dt>Version History:
<dd><a href="https://github.com/whatwg/html-differences/commits">https://github.com/whatwg/html-differences/commits</a>
<dt class="not-whatwg">Previous Versions:</dt>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2012/WD-html5-diff-20120329/">http://www.w3.org/TR/2012/WD-html5-diff-20120329/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2011/WD-html5-diff-20110525/">http://www.w3.org/TR/2011/WD-html5-diff-20110525/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2011/WD-html5-diff-20110405/">http://www.w3.org/TR/2011/WD-html5-diff-20110405/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2011/WD-html5-diff-20110405/">http://www.w3.org/TR/2011/WD-html5-diff-20110405/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2011/WD-html5-diff-20110113/">http://www.w3.org/TR/2011/WD-html5-diff-20110113/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2010/WD-html5-diff-20101019/">http://www.w3.org/TR/2010/WD-html5-diff-20101019/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2010/WD-html5-diff-20100624/">http://www.w3.org/TR/2010/WD-html5-diff-20100624/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2010/WD-html5-diff-20100304/">http://www.w3.org/TR/2010/WD-html5-diff-20100304/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2009/WD-html5-diff-20090825/">http://www.w3.org/TR/2009/WD-html5-diff-20090825/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2009/WD-html5-diff-20090423/">http://www.w3.org/TR/2009/WD-html5-diff-20090423/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2009/WD-html5-diff-20090212/">http://www.w3.org/TR/2009/WD-html5-diff-20090212/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2008/WD-html5-diff-20080610/">http://www.w3.org/TR/2008/WD-html5-diff-20080610/</a></dd>
<dd class="not-whatwg"><a href="http://www.w3.org/TR/2008/WD-html5-diff-20080122/">http://www.w3.org/TR/2008/WD-html5-diff-20080122/</a></dd>
<dt>Editor:</dt>
<dd>Simon Pieters
(<a href="http://www.opera.com/">Opera Software ASA</a>)
<<a href="mailto:simonp@opera.com">simonp@opera.com</a>></dd>
<dt>Previous Editor:</dt>
<dd><a href="http://annevankesteren.nl/">Anne van Kesteren</a>
<<a href="mailto:annevk@annevk.nl">annevk@annevk.nl</a>></dd>
</dl>
<script async="" class="not-tr" src="https://w3c-test.org/resources.whatwg.org/file-bug.js"></script>
<div class="not-whatwg">
<!--begin-copyright-->
<p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 2013 <a href="http://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="http://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="http://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="http://www.keio.ac.jp/">Keio</a>, <a href="http://ev.buaa.edu.cn/">Beihang</a>), All Rights Reserved. W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.</p>
<!--end-copyright--></div>
</div>
<hr>
<h2 class="no-num no-toc" id="abstract">Abstract</h2>
<p>HTML is the core language of the World Wide Web. The W3C publish HTML5 and HTML5.1.
The WHATWG publishes HTML, which is a rough superset of W3C HTML5.1.
"HTML differences from HTML4" describes the
differences of these documents from HTML4, and calls out cases where they differ from
each other. This document may not provide accurate information as
the specifications are still actively in development. When in doubt, always
check the specifications themselves. <a href="#refsHTML5">[HTML5]</a>
<a href="#refsHTML5NIGHTLY">[HTML5NIGHTLY]</a> <a href="#refsHTML">[HTML]</a></p>
<div class="not-whatwg">
<h2 class="no-num no-toc" id="sotd">Status of this Document</h2>
<p><i>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 <a href="http://www.w3.org/TR/">W3C technical reports index</a>
at http://www.w3.org/TR/.</i></p>
<p>This is the 2 May 2013 Editor's Draft produced by the
<a href="http://www.w3.org/html/wg/">HTML Working Group</a>, part of the
<a href="http://www.w3.org/MarkUp/Activity">HTML Activity</a>. The
Working Group intends to publish this document as a
<a href="http://www.w3.org/2005/10/Process-20051014/#WGNote">Working
Group Note</a>.
The appropriate forum for comments is
<a href="https://www.w3.org/Bugs/Public/enter_bug.cgi?product=HTML%20WG&component=HTML5%20differences%20from%20HTML4">W3C
Bugzilla</a>. (<a href="mailto:public-html-comments@w3.org">public-html-comments@w3.org</a>,
a mailing list with a
<a href="http://lists.w3.org/Archives/Public/public-html-comments/" title="Archive for HTML comments mailing-list">public
archive</a>, is no longer used for tracking comments.)</p>
<p>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.</p>
<p>This document was produced by a group operating under the
<a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February
2004 W3C Patent Policy</a>. W3C maintains a
<a href="http://www.w3.org/2004/01/pp-impl/40318/status" rel="disclosure">public
list of any patent disclosures</a> 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
<a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with
<a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
6 of the W3C Patent Policy</a>.</p>
</div>
<h2 class="no-num no-toc" id="toc">Table of Contents</h2>
<!--begin-toc-->
<ol class="toc">
<li><a href="#introduction"><span class="secno">1 </span>Introduction</a>
<ol class="toc">
<li><a href="#scope"><span class="secno">1.1 </span>Scope of this document</a></li>
<li><a href="#history"><span class="secno">1.2 </span>History of HTML</a></li>
<li><a href="#open-issues"><span class="secno">1.3 </span>Open Issues</a></li>
<li><a href="#backwards-compatible"><span class="secno">1.4 </span>Backwards Compatible</a></li>
<li><a href="#development-model"><span class="secno">1.5 </span>Development Model</a></ol></li>
<li><a href="#syntax"><span class="secno">2 </span>Syntax</a>
<ol class="toc">
<li><a href="#character-encoding"><span class="secno">2.1 </span>Character Encoding</a></li>
<li><a href="#doctype"><span class="secno">2.2 </span>The Doctype</a></li>
<li><a href="#mathml-svg"><span class="secno">2.3 </span>MathML and SVG</a></li>
<li><a href="#syntax-misc"><span class="secno">2.4 </span>Miscellaneous</a></ol></li>
<li><a href="#language"><span class="secno">3 </span>Language</a>
<ol class="toc">
<li><a href="#new-elements"><span class="secno">3.1 </span>New Elements</a></li>
<li><a href="#new-attributes"><span class="secno">3.2 </span>New Attributes</a></li>
<li><a href="#changed-elements"><span class="secno">3.3 </span>Changed Elements</a></li>
<li><a href="#changed-attributes"><span class="secno">3.4 </span>Changed Attributes</a></li>
<li><a href="#obsolete-elements"><span class="secno">3.5 </span>Obsolete Elements</a></li>
<li><a href="#obsolete-attributes"><span class="secno">3.6 </span>Obsolete Attributes</a></ol></li>
<li><a href="#content-model"><span class="secno">4 </span>Content Model</a></li>
<li><a href="#apis"><span class="secno">5 </span>APIs</a>
<ol class="toc">
<li><a href="#new-apis"><span class="secno">5.1 </span>New APIs</a></li>
<li><a href="#changed-apis"><span class="secno">5.2 </span>Changed APIs</a></li>
<li><a href="#document-extensions"><span class="secno">5.3 </span>Extensions to
<code>Document</code></a></li>
<li><a href="#htmlelement-extensions"><span class="secno">5.4 </span>Extensions to <code>HTMLElement</code></a></li>
<li><a href="#other-extensions"><span class="secno">5.5 </span>Extensions to Other Interfaces</a></li>
<li><a href="#obsolete-apis"><span class="secno">5.6 </span>Obsolete APIs</a></ol></li>
<li><a href="#changelog"><span class="secno">6 </span>HTML Changelogs</a>
<ol class="toc">
<li><a href="#changes-2012-09-14"><span class="secno">6.1 </span>Changes from 14 September 2012 to 30 April 2013</a></li>
<li><a href="#changes-2012-03-29"><span class="secno">6.2 </span>Changes from 29 March 2012 to 14 September 2012</a></li>
<li><a href="#changes-2011-05-25"><span class="secno">6.3 </span>Changes from 25 May 2011 to 29 March 2012</a></li>
<li><a href="#changes-2011-04-05"><span class="secno">6.4 </span>Changes from 5 April 2011 to 25 May 2011</a></li>
<li><a href="#changes-2011-01-13"><span class="secno">6.5 </span>Changes from 13 January 2011 to 5 April 2011</a></li>
<li><a href="#changes-2010-10-19"><span class="secno">6.6 </span>Changes from 19 October 2010 to 13 January 2011</a></li>
<li><a href="#changes-2010-06-24"><span class="secno">6.7 </span>Changes from 24 June 2010 to 19 October 2010</a></li>
<li><a href="#changes-2010-03-04"><span class="secno">6.8 </span>Changes from 4 March 2010 to 24 June 2010</a></li>
<li><a href="#changes-2009-08-25"><span class="secno">6.9 </span>Changes from 25 August 2009 to 4 March 2010</a></li>
<li><a href="#changes-2009-04-23"><span class="secno">6.10 </span>Changes from 23 April 2009 to 25 August 2009</a></li>
<li><a href="#changes-2009-02-12"><span class="secno">6.11 </span>Changes from 12 February 2009 to 23 April 2009</a></li>
<li><a href="#changes-2008-06-10"><span class="secno">6.12 </span>Changes from 10 June 2008 to 12 February 2009</a></li>
<li><a href="#changes-2008-01-22"><span class="secno">6.13 </span>Changes from 22 January 2008 to 10 June 2008</a></ol></li>
<li><a class="no-num" href="#acknowledgments">Acknowledgments</a></li>
<li><a class="no-num" href="#references">References</a></ol>
<!--end-toc-->
<h2 id="introduction"><span class="secno">1 </span>Introduction</h2>
<h3 id="scope"><span class="secno">1.1 </span>Scope of this document</h3>
<p>This document covers the W3C HTML5 specification, W3C HTML5.1 specification, and
the WHATWG HTML standard. These are referred to as if they were a single specification
as "the HTML specification" or simply "HTML" when something applies equally to all of
them, and otherwise they are called out explicitly.
<h3 id="history"><span class="secno">1.2 </span>History of HTML</h3>
<p>HTML has been in continuous evolution since it was introduced to the
Internet in the early 1990s. Some features were introduced in
specifications; others were introduced in software releases. In some
respects, implementations and Web developer practices have converged with each
other and with specifications and standards, but in other ways, they
have diverged.</p>
<p>HTML4 became a W3C Recommendation in 1997. While it continues
to serve as a rough guide to many of the core features of HTML, it does
not provide enough information to build implementations that
interoperate with each other and, more importantly, with a critical mass
of deployed content. The same goes for XHTML1, which defines an
XML serialization for HTML4, and DOM Level 2 HTML, which defines
JavaScript APIs for both HTML and XHTML. HTML replaces these documents. <a href="#refsDOM2HTML">[DOM2HTML]</a>
<a href="#refsHTML4">[HTML4]</a>
<a href="#refsXHTML1">[XHTML1]</a>
<p>The HTML specification reflects an effort, started in 2004, to study
contemporary HTML implementations and deployed content. The specification:</p>
<ol>
<li>Defines a single language called HTML which can be written
in HTML syntax and in XML syntax.</li>
<li>Defines detailed processing models to foster interoperable
implementations.</li>
<li>Improves markup for documents.</li>
<li>Introduces markup and APIs for emerging idioms, such as Web
applications.</li>
</ol>
<h3 id="open-issues"><span class="secno">1.3 </span>Open Issues</h3>
<p>The contents of HTML, as well as the contents of this document which depend on
HTML, are still being discussed on the HTML Working Group
and WHATWG mailing lists. The open issues are linked from the HTML specification.</p>
<h3 id="backwards-compatible"><span class="secno">1.4 </span>Backwards Compatible</h3>
<p>HTML is defined in a way that it is backwards compatible with
the way user agents handle deployed content. To keep the
language relatively simple for Web developers, several elements and attributes
are not included, as outlined in the other sections of this document,
such as presentational elements that are better dealt with using
CSS.</p>
<p>User agents, however, will always have to support these older
elements and attributes and this is why the HTML specification clearly
separates requirements for Web developers (referred to as "authors" in the
specification) and user agents. For instance, this
means that Web developers cannot use the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#isindex-0">isindex</a></code> or the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#plaintext">plaintext</a></code> element, but user agents are required to support
them in a way that is compatible with how these elements need to behave
for compatibility with deployed content.</p>
<p>Since HTML has separate conformance requirements for Web developers
and user agents there is no longer a need for marking features
"deprecated".</p>
<h3 id="development-model"><span class="secno">1.5 </span>Development Model</h3>
<p>The HTML4 specification reached Recommendation status before it was completely
implemented in user agents. HTML4 still is not completely implemented, because it
contains various bugs that have been fixed in the current HTML specification, which
user agents are much closer to than HTML4.
<p>The WHATWG HTML standard is under continual development where bugs are fixed
and new features are introduced over time. Features can also be removed from the
specification if they lack implementor interest or are not being used by Web developers, or
for other reasons. The WHATWG does not publish frozen snapshots.
<p>The W3C HTML5 specification is trying to reach Recommendation status. New features
are generally not added unless they are implemented by at least two browsers and has
tests demonstrating interoperability. Minor bug fixes can be applied. This means that
it may contain bugs that have been fixed in WHATWG HTML or W3C HTML5.1, or both.
<p>The W3C HTML5.1 specification is similar to WHATWG HTML: it is under continual development where bugs are fixed and new features are introduced over time,
and features can be removed from the specification for the same reasons as with WHATWG HTML. It cherry-picks changes from the WHATWG HTML standard and also
gets direct changes. It is expected to eventually go through the same procedure as W3C HTML5, and then a new version will be minted.
<h2 id="syntax"><span class="secno">2 </span>Syntax</h2>
<p>HTML defines an HTML syntax that is
compatible with HTML4 and XHTML1 documents published on the
Web, but is not compatible with the more esoteric SGML features of
HTML4, such as
<a href="http://www.w3.org/TR/1999/REC-html401-19991224/appendix/notes.html#h-B.3.6">processing instructions</a>
and
<a href="http://www.w3.org/TR/1999/REC-html401-19991224/appendix/notes.html#h-B.3.7">shorthand markup</a>
as these are not supported by most user agents. Documents using the HTML
syntax are served with the <code>text/html</code> media
type.</p>
<p>HTML also defines detailed parsing rules (including "error
handling") for this syntax which are largely compatible with HTML4-era
implementations. User agents must use these rules for resources that
have the <code>text/html</code> media type. Here is an example document
that conforms to the HTML syntax:</p>
<pre><code><!doctype html>
<html>
<head>
<meta charset="UTF-8">
<title>Example document</title>
</head>
<body>
<p>Example paragraph</p>
</body>
</html></code></pre>
<p>The other syntax that can be used for HTML is XML. This syntax
is compatible with XHTML1 documents and implementations. Documents
using this syntax need to be served with an XML media type and elements
need to be put in the <code>http://www.w3.org/1999/xhtml</code>
namespace following the rules set forth by the XML specifications.
<a href="#refsXML">[XML]</a>
<p>Below is an example document that conforms to the XML syntax of
HTML. Note that XML documents must be served with an XML media type
such as <code>application/xhtml+xml</code> or
<code>application/xml</code>.</p>
<pre><code><?xml version="1.0" encoding="UTF-8"?>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Example document</title>
</head>
<body>
<p>Example paragraph</p>
</body>
</html></code></pre>
<h3 id="character-encoding"><span class="secno">2.1 </span>Character Encoding</h3>
<p>For the HTML syntax, Web developers are required to declare the
character encoding. There are three ways to do that:</p>
<ul>
<li>At the transport level. By using the HTTP <code>Content-Type</code>
header for instance.</li>
<li>Using a Unicode Byte Order Mark (BOM) character at the start of
the file. This character provides a signature for the encoding
used.</li>
<li>Using a <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-meta-element">meta</a></code> element with a <code class="external" title="attr-meta-charset"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-meta-charset">charset</a></code>
attribute that specifies the encoding within the first 1024 bytes of
the document. For instance, <code><meta charset="UTF-8"></code>
could be used to specify the UTF-8 encoding. This replaces the need
for
<code><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></code>
although that syntax is still allowed.</li>
</ul>
<p>For the XML syntax, Web developers have to use the rules as set forth in the
XML specifications to set the character encoding.</p>
<h3 id="doctype"><span class="secno">2.2 </span>The Doctype</h3>
<p>The HTML syntax requires a doctype to be specified to ensure
that the browser renders the page in standards mode. The doctype has no
other purpose. <a href="#refsDOCTYPE">[DOCTYPE]</a>
<p>The doctype declaration for the HTML syntax is <code><!DOCTYPE html></code> and is
case-insensitive. Doctypes from earlier versions of
HTML were longer because the HTML language was SGML-based and therefore
required a reference to a DTD. This is no longer the case and
the doctype is only needed to enable standards mode for documents
written using the HTML syntax. Browsers already do this for
<code><!DOCTYPE html></code>.</p>
<p>To support legacy markup generators that cannot generate the preferred
short doctype, the doctype <code><!DOCTYPE html SYSTEM
"about:legacy-compat"></code> is allowed in the HTML syntax.
<p>The strict doctypes for HTML 4.0, HTML 4.01, XHTML 1.0 as well as XHTML
1.1 are also allowed (but are discouraged) in the HTML syntax.
<p>In the XML syntax, any doctype declaration may be used, or it may be
omitted altogether. Documents with an XML media type are always handled in
standards mode.
<h3 id="mathml-svg"><span class="secno">2.3 </span>MathML and SVG</h3>
<p>The HTML syntax allows for MathML and SVG elements to
be used inside a document. An <code>math</code> or <code>svg</code> start
tag causes the HTML parser to switch to a special insertion mode which puts
elements and attributes in the appropriate namespaces, does case fixups for
elements and attributes that have mixed case, and supports the empty-element
syntax as in XML. The syntax is still case-insensitive and attributes allow
the same syntax as for HTML elements. Namespace declarations may be omitted.
CDATA sections are supported in this insertion mode.
<p>Some MathML and SVG elements cause the parser to switch back to "HTML
mode", e.g. <code>mtext</code> and <code>foreignObject</code>, so you can
use HTML elements or a new <code>math</code> or <code>svg</code> element.
<p>For instance, a very simple document using some of the
minimal syntax features could look like:</p>
<pre><code><!doctype html>
<title>SVG in text/html</title>
<p>
A green circle:
<strong><svg> <circle r="50" cx="50" cy="50" fill="green"/> </svg></strong>
</p></code></pre>
<h3 id="syntax-misc"><span class="secno">2.4 </span>Miscellaneous</h3>
<p>There are a few other changes in the HTML syntax worthy of mentioning:</p>
<ul>
<li><p>The <code>&lang;</code> and <code>&rang;</code> named character
references now expand to U+27E8 and U+27E9 instead of U+2329 and U+232A,
respectively.
<li><p>Many new named character references have been added, including all from
MathML.
<li><p>Void elements (known as "EMPTY" in HTML4) are allowed to have a
trailing slash.
<li><p>The ampersand (<code>&</code>) may be left unescaped in some more
cases compared to HTML4.
<li><p>Attributes have to be separated by at least one whitespace character.
<li><p>Attributes with an empty value may be written as just the attribute
name omitting the equals sign and the value, even if it's not a boolean
attribute. (HTML4 actually allowed using only the attribute
<em>value</em> and omitting the attribute name, for enumerated attributes,
but this was not supported in browsers.)
<li><p>Attributes omitting quotes for the value are allowed to use a larger
set of characters compared to HTML4.
<li><p>The <code>optgroup</code> end tag is now optional.
<li><p>The <code>colgroup</code> start tag is now optional and is inferred by
the HTML parser.
</ul>
<h2 id="language"><span class="secno">3 </span>Language</h2>
<p>This section is split up in several subsections to more clearly
illustrate the various differences there are from HTML4.</p>
<h3 id="new-elements"><span class="secno">3.1 </span>New Elements</h3>
<p>The following elements have been introduced for better structure:</p>
<ul>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-section-element">section</a></code>
represents a generic document or application section. It can be
<a class="external" href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#headings-and-sections" title="Headings and sections">used together</a>
with the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-h1-element">h1</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-h2-element">h2</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-h3-element">h3</a></code>,
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-h4-element">h4</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-h5-element">h5</a></code>, and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-h6-element">h6</a></code> elements to
indicate the document structure.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-article-element">article</a></code>
represents an independent piece of content of a document, such as a
blog entry or newspaper article.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/grouping-content.html#the-main-element">main</a></code>
can be used as a container for the dominant contents of another element, such as
the main content of the page.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-aside-element">aside</a></code>
represents a piece of content that is only slightly related to the
rest of the page.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-hgroup-element">hgroup</a></code>
represents the header of a section.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-header-element">header</a></code>
represents a group of introductory or navigational aids.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-footer-element">footer</a></code>
represents a footer for a section and can contain information about
the author, copyright information, etc.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-nav-element">nav</a></code>
represents a section of the document intended for navigation.</li>
<li>
<p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/grouping-content.html#the-figure-element">figure</a></code>
represents a piece of self-contained flow content, typically
referenced as a single unit from the main flow of the document.</p>
<pre><code><figure>
<video src="example.webm" controls></video>
<figcaption>Example</figcaption>
</figure></code></pre>
<p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/grouping-content.html#the-figcaption-element">figcaption</a></code> can be used as caption (it is optional).</p>
</li>
</ul>
<p>Then there are several other new elements:</p>
<ul>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-video-element">video</a></code> and
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-audio-element">audio</a></code> for multimedia content. Both
provide an API so application Web developers can script their own user
interface, but there is also a way to trigger a user interface
provided by the user agent. <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-source-element">source</a></code>
elements are used together with these elements if there are multiple
streams available of different types.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-track-element">track</a></code> provides text tracks
for the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-video-element">video</a></code> element.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#the-embed-element">embed</a></code> is used for plugin
content.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-mark-element">mark</a></code> represents a run of
text in one document marked or highlighted for reference purposes, due
to its relevance in another context.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-progress-element">progress</a></code> represents a
completion of a task, such as downloading or when performing a series
of expensive operations.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-meter-element">meter</a></code> represents a
measurement, such as disk usage.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-time-element">time</a></code> represents a date
and/or time.
<li><p>WHATWG HTML and W3C HTML5.1 has <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-data-element">data</a></code> which
allows content to be annotated with a machine-readable value.
<li><p>WHATWG HTML and W3C HTML5.1 has <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/commands.html#the-dialog-element">dialog</a></code> for showing a dialog.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-ruby-element">ruby</a></code>,
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-rt-element">rt</a></code>, and
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-rp-element">rp</a></code> allow for marking up ruby
annotations.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-bdi-element">bdi</a></code> represents a span of
text that is to be isolated from its surroundings for the purposes of
bidirectional text formatting.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-wbr-element">wbr</a></code> represents a line break
opportunity.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#the-canvas-element">canvas</a></code> is used for rendering
dynamic bitmap graphics on the fly, such as graphs or games.
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#the-menuitem-element">menuitem</a></code>
represents a command the user can invoke from a popup menu.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#the-details-element">details</a></code>
represents additional information or controls which the user can
obtain on demand. The
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#the-summary-element">summary</a></code>
element provides its summary, legend, or caption.</li>
<li>
<p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-datalist-element">datalist</a></code>
together with the a new <code class="external" title="attr-input-list"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-list">list</a></code> attribute for
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> can be used to make comboboxes:</p>
<pre><code><input <strong>list="browsers"</strong>>
<datalist <strong>id="browsers"</strong>>
<option value="Safari">
<option value="Internet Explorer">
<option value="Opera">
<option value="Firefox">
</datalist></code></pre>
</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-keygen-element">keygen</a></code>
represents control for key pair generation.</li>
<li><p><code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-output-element">output</a></code>
represents some type of output, such as from a calculation done
through scripting.</li>
</ul>
<p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> element's <code class="external" title="attr-input-type"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#attr-input-type">type</a></code> attribute now has the
following new values:</p>
<ul>
<li><code class="external" title="attr-input-type-tel"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#telephone-state-(type=tel)">tel</a></code>
<li><code class="external" title="attr-input-type-search"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#text-(type=text)-state-and-search-state-(type=search)">search</a></code>
<li><code class="external" title="attr-input-type-url"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#url-state-(type=url)">url</a></code>
<li><code class="external" title="attr-input-type-email"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#e-mail-state-(type=email)">email</a></code>
<li><code class="external" title="attr-input-type-datetime"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#date-and-time-state-(type=datetime)">datetime</a></code>
<li><code class="external" title="attr-input-type-date"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#date-state-(type=date)">date</a></code>
<li><code class="external" title="attr-input-type-month"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#month-state-(type=month)">month</a></code>
<li><code class="external" title="attr-input-type-week"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#week-state-(type=week)">week</a></code>
<li><code class="external" title="attr-input-type-time"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#time-state-(type=time)">time</a></code>
<li><code class="external" title="attr-input-type-datetime-local"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#local-date-and-time-state-(type=datetime-local)">datetime-local</a></code>
<li><code class="external" title="attr-input-type-number"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#number-state-(type=number)">number</a></code>
<li><code class="external" title="attr-input-type-range"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#range-state-(type=range)">range</a></code>
<li><code class="external" title="attr-input-type-color"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#color-state-(type=color)">color</a></code>
</ul>
<p>The idea of these new types is that the user agent can provide the user
interface, such as a calendar date picker or integration with the user's
address book, and submit a defined format to the server. It gives the user a
better experience as his input is checked before sending it to the server
meaning there is less time to wait for feedback.</p>
<h3 id="new-attributes"><span class="secno">3.2 </span>New Attributes</h3>
<p>Several attributes have been introduced to various elements
that were already part of HTML4:</p>
<ul>
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-a-element">a</a></code> and
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-map-element.html#the-area-element">area</a></code> elements have the new
<code class="external" title="attr-hyperlink-download"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#attr-hyperlink-download">download</a></code> attribute
in WHATWG HTML and W3C HTML5.1. WHATWG HTML also has the
<code class="external" title="attr-hyperlink-ping"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#ping">ping</a></code> attribute.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-map-element.html#the-area-element">area</a></code> element, for consistency with the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-a-element">a</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-link-element">link</a></code> elements, now also has the
<code class="external" title="attr-hyperlink-hreflang"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#attr-hyperlink-hreflang">hreflang</a></code>, <code class="external" title="attr-hyperlink-type"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#attr-hyperlink-type">type</a></code> and <code class="external" title="attr-hyperlink-rel"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#attr-hyperlink-rel">rel</a></code> attributes.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-base-element">base</a></code> element can now have a <code class="external" title="attr-base-target"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-base-target">target</a></code>
attribute as well, mainly for consistency with the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-a-element">a</a></code> element. (This is already widely supported.)
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-meta-element">meta</a></code> element has a <code class="external" title="attr-meta-charset"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-meta-charset">charset</a></code>
attribute now as this was already widely supported and provides a nice
way to specify the
<a href="#character-encoding">character encoding</a> for the document.
<li><p>In WHATWG HTML and W3C HTML5.1, the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/tabular-data.html#the-table-element">table</a></code>
element now has a <code class="external" title="attr-table-sortable"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/tabular-data.html#attr-table-sortable">sortable</a></code> attribute and the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/tabular-data.html#the-th-element">th</a></code> element has a
<code class="external" title="attr-th-sorted"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/tabular-data.html#attr-th-sorted">sorted</a></code> attribute, which provide a means to sort
table columns.
<li><p>A new <code class="external" title="attr-fe-autofocus"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fe-autofocus">autofocus</a></code> attribute can be specified on the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> (except when the <code class="external" title="attr-input-type"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#attr-input-type">type</a></code> attribute is
<code class="external" title="attr-input-type-hidden"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#hidden-state-(type=hidden)">hidden</a></code>), <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-select-element">select</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-textarea-element">textarea</a></code> and
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-button-element">button</a></code> elements. It provides a declarative way to focus a
form control during page load. Using this feature should enhance the
user experience compared to focusing the element with script as the user can turn it off if the user does not like
it, for instance.
<li>
<p>A new <code class="external" title="attr-input-placeholder"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-placeholder">placeholder</a></code> attribute can be specified on
the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-textarea-element">textarea</a></code> elements. It
represents a hint intended to aid the user with data entry.</p>
<pre><code><input type=email <strong>placeholder="a@b.com"</strong>></code></pre>
</li>
<li>
<p>The new <code class="external" title="attr-fae-form"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fae-form">form</a></code> attribute for <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code>,
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-output-element">output</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-select-element">select</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-textarea-element">textarea</a></code>,
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-button-element">button</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-label-element">label</a></code>, <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#the-object-element">object</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-fieldset-element">fieldset</a></code> elements allows for
controls to be associated with a form. These elements can now be
placed anywhere on a page, not just as descendants of the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-form-element">form</a></code> element, and still be associated with a <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-form-element">form</a></code>.</p>
<pre><table>
<tr>
<th>Key
<th>Value
<th>Action
<tr>
<td><form <strong>id=1</strong>><input name=1-key></form>
<td><input <strong>form=1</strong> name=1-value>
<td><button <strong>form=1</strong> name=1-action value=save>✓</button>
<button <strong>form=1</strong> name=1-action value=delete>✗</button>
...
</table></pre>
</li>
<li><p>The new <code class="external" title="attr-input-required"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-required">required</a></code> attribute applies to
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> (except when the <code class="external" title="attr-input-type"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#attr-input-type">type</a></code> attribute is
<code class="external" title="attr-input-type-hidden"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#hidden-state-(type=hidden)">hidden</a></code>, <code class="external" title="attr-input-type-image"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#image-button-state-(type=image)">image</a></code> or some button type such as
<code class="external" title="attr-input-type-submit"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#submit-button-state-(type=submit)">submit</a></code>), <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-select-element">select</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-textarea-element">textarea</a></code>. It indicates that the user
has to fill in a value in order to submit the form. For <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-select-element">select</a></code>, the first <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-option-element">option</a></code> element has to be a placeholder with an empty value.
<pre><code><label>Color: <select name=color <strong>required</strong>>
<option <strong>value=""</strong>>Choose one
<option>Red
<option>Green
<option>Blue
</select></label></code></pre>
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-fieldset-element">fieldset</a></code> element now allows the
<code class="external" title="attr-fieldset-disabled"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#attr-fieldset-disabled">disabled</a></code> attribute which disables all descendant controls (excluding those that are descendants of the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-legend-element">legend</a></code> element)
when specified, and the <code class="external" title="attr-fe-name"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fe-name">name</a></code> attribute which can be used for script access.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> element has several new attributes to
specify constraints: <code class="external" title="attr-fe-autocomplete"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fe-autocomplete">autocomplete</a></code>, <code class="external" title="attr-input-min"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-min">min</a></code>,
<code class="external" title="attr-input-max"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-max">max</a></code>, <code class="external" title="attr-input-multiple"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-multiple">multiple</a></code>, <code class="external" title="attr-input-pattern"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-pattern">pattern</a></code> and
<code class="external" title="attr-input-step"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-step">step</a></code>. As mentioned before it also has a new
<code class="external" title="attr-input-list"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/common-input-element-attributes.html#attr-input-list">list</a></code> attribute which can be used together with the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-datalist-element">datalist</a></code> element. It also now has the <code class="external" title="attr-dim-width"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-map-element.html#attr-dim-width">width</a></code> and <code class="external" title="attr-dim-height"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-map-element.html#attr-dim-height">height</a></code> attributes to specify the dimensions of the image when using <code>type=image</code>.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-textarea-element">textarea</a></code> elements have
a new attribute named <code class="external" title="attr-fe-dirname"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fe-dirname">dirname</a></code> that causes the
directionality of the control as set by the user to be submitted as
well.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-textarea-element">textarea</a></code> element also has two new attributes,
<code class="external" title="attr-textarea-maxlength"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#attr-textarea-maxlength">maxlength</a></code> and <code class="external" title="attr-textarea-wrap"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#attr-textarea-wrap">wrap</a></code> which control max input
length and submitted line wrapping behavior, respectively.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-form-element">form</a></code> element has a <code class="external" title="attr-fs-novalidate"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-novalidate">novalidate</a></code>
attribute that can be used to disable form validation submission (i.e.
the form can always be submitted).
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-button-element">button</a></code> elements have
<code class="external" title="attr-fs-formaction"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-formaction">formaction</a></code>, <code class="external" title="attr-fs-formenctype"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-formenctype">formenctype</a></code>,
<code class="external" title="attr-fs-formmethod"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-formmethod">formmethod</a></code>, <code class="external" title="attr-fs-formnovalidate"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-formnovalidate">formnovalidate</a></code>, and
<code class="external" title="attr-fs-formtarget"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-formtarget">formtarget</a></code> as new attributes. If present, they override
the <code class="external" title="attr-fs-action"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-action">action</a></code>, <code class="external" title="attr-fs-enctype"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-enctype">enctype</a></code>, <code class="external" title="attr-fs-method"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-method">method</a></code>,
<code class="external" title="attr-fs-novalidate"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-novalidate">novalidate</a></code>, and <code class="external" title="attr-fs-target"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fs-target">target</a></code> attributes on the
<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/forms.html#the-form-element">form</a></code> element.</p>
<li><p>In WHATWG HTML, the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#the-input-element">input</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-textarea-element">textarea</a></code> have an <code class="external" title="attr-fe-inputmode"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#attr-fe-inputmode">inputmode</a></code> attribute.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#the-menu-element">menu</a></code> element has two new attributes:
<code class="external" title="attr-menu-type"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#attr-menu-type">type</a></code> and <code class="external" title="attr-menu-label"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#attr-menu-label">label</a></code>. They
allow the element to transform into a menu as found in typical user
interfaces as well as providing for context menus in conjunction with the
global <code class="external" title="attr-contextmenu"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#attr-contextmenu">contextmenu</a></code> attribute.
<li><p>In WHATWG HTML and W3C HTML5.1, the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-button-element">button</a></code>
element has a new <code class="external" title="attr-button-menu"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#attr-button-menu">menu</a></code>
attribute, used together with popup menus.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-style-element">style</a></code> element has a new <code class="external" title="attr-style-scoped"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-style-scoped">scoped</a></code>
attribute which can be used to enable scoped style sheets. Style rules
within such a <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-style-element">style</a></code> element only apply to the local tree.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/scripting-1.html#the-script-element">script</a></code> element has a new attribute called
<code class="external" title="attr-script-async"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/scripting-1.html#attr-script-async">async</a></code> that influences script loading and execution.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-html-element">html</a></code> element has a new attribute called
<code class="external" title="attr-html-manifest"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-html-manifest">manifest</a></code> that points to an application cache manifest
used in conjunction with the API for offline Web applications.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-link-element">link</a></code> element has a new attribute called
<code class="external" title="attr-link-sizes"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#attr-link-sizes">sizes</a></code>. It can be used in conjunction with the
<code class="external" title="rel-icon"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#rel-icon">icon</a></code> relationship (set through the <code class="external" title="attr-link-rel"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-link-rel">rel</a></code>
attribute; can be used for e.g. favicons) to indicate the size of the
referenced icon. Thus allowing for icons of distinct dimensions.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/grouping-content.html#the-ol-element">ol</a></code> element has a new attribute called
<code class="external" title="attr-ol-reversed"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/grouping-content.html#attr-ol-reversed">reversed</a></code>. When present, it indicates that the list order
is descending.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#the-iframe-element">iframe</a></code> element has three new attributes called
<code class="external" title="attr-iframe-sandbox"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#attr-iframe-sandbox">sandbox</a></code>, <code class="external" title="attr-iframe-seamless"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#attr-iframe-seamless">seamless</a></code>, and <code class="external" title="attr-iframe-srcdoc"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#attr-iframe-srcdoc">srcdoc</a></code>
which allow for sandboxing content, e.g. blog comments.</li>
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#the-object-element">object</a></code> element has a new attribute called <code class="external" title="attr-object-typemustmatch"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html#attr-object-typemustmatch">typemustmatch</a></code> which allows safer embedding of external resources.
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/embedded-content-1.html#the-img-element">img</a></code> element has a new attribute called
<code class="external" title="attr-img-crossorigin"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/embedded-content-1.html#attr-img-crossorigin">crossorigin</a></code> to use CORS in the fetch and if it is successful, allows the image data to be
read with the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#the-canvas-element">canvas</a></code> API. In WHATWG HTML and W3C HTML 5.1, the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/scripting-1.html#the-script-element">script</a></code> element has a
<code class="external" title="attr-script-crossorigin"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/scripting-1.html#attr-script-crossorigin">crossorigin</a></code> attribute to allow script
<a class="external" href="http://www.whatwg.org/specs/web-apps/current-work/multipage/webappapis.html#report-the-error" title="report the error">errors to be reported</a> to <code class="external" title="handler-onerror"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/webappapis.html#handler-onerror">onerror</a></code>
with information about the error. WHATWG HTML and W3C HTML 5.1 also has the <code class="external" title="attr-link-crossorigin"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-link-crossorigin">crossorigin</a></code>
attribute on the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-link-element">link</a></code> element.
<li><p>In WHATWG HTML, the <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/embedded-content-1.html#the-img-element">img</a></code> element has a new attribute called <code class="external" title="attr-img-srcset"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/embedded-content-1.html#attr-img-srcset">srcset</a></code> to support multiple images for different resolutions and different images for different viewport sizes.
</ul>
<p>Several attributes from HTML4 now apply to all elements. These
are called global attributes: <code class="external" title="attr-accesskey"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/editing.html#the-accesskey-attribute">accesskey</a></code>, <code class="external" title="attr-class"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#classes">class</a></code>, <code class="external" title="attr-dir"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#the-dir-attribute">dir</a></code>,
<code class="external" title="attr-id"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#the-id-attribute">id</a></code>, <code class="external" title="attr-dir"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#the-dir-attribute">lang</a></code>, <code class="external" title="attr-style"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#the-style-attribute">style</a></code>,
<code class="external" title="attr-tabindex"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/editing.html#attr-tabindex">tabindex</a></code> and <code class="external" title="attr-title"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#the-title-attribute">title</a></code>. Additionally, XHTML 1.0
only allowed <code>xml:space</code> on some elements, which is now allowed
on all elements in XHTML documents.</p>
<p>There are also several new global attributes:</p>
<ul>
<li><p>The <code class="external" title="attr-contenteditable"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/editing.html#attr-contenteditable">contenteditable</a></code> attribute indicates that
the element is an editable area. The user can change the contents of the
element and manipulate the markup.
<li><p>The <code class="external" title="attr-contextmenu"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#attr-contextmenu">contextmenu</a></code> attribute can be used to point
to a context menu provided by the Web developer.
<li><p>The <code class="external" title="attr-data-*"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#attr-data-*">data-<var>*</var></a></code> collection of Web developer-defined
attributes. Web developers can define any attribute they want as long as they
prefix it with <code>data-</code> to avoid clashes with future versions of
HTML. These are intended to be used to store custom data to be consumed by
the Web page or application itself. They are <em>not</em> intended for
data to be consumed by other parties (e.g. user agents).
<li><p>The <code class="external" title="attr-draggable"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/dnd.html#the-draggable-attribute">draggable</a></code> and <code class="external" title="attr-dropzone"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/dnd.html#the-dropzone-attribute">dropzone</a></code> attributes can be used together with
the new drag & drop API.
<li><p>The <code class="external" title="attr-hidden"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/editing.html#the-hidden-attribute">hidden</a></code>
attribute indicates that an element is not yet, or is no longer, relevant.
<li><p>WHATWG HTML has the <code class="external" title="attr-inert"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/editing.html#the-inert-attribute">inert</a></code> attribute, intended to make <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/commands.html#the-dialog-element">dialog</a></code> elements modal.
<li><p>The <code class="external" title="wai-aria"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#wai-aria">role</a></code> and
<code class="external" title="wai-aria"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#wai-aria">aria-<var>*</var></a></code>
collection attributes which can be used to instruct assistive
technology.</li>
<li><p>The <code class="external" title="attr-spellcheck"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/editing.html#attr-spellcheck">spellcheck</a></code> attribute allows for hinting
whether content can be checked for spelling or not.
<li><p>The <code class="external" title="attr-translate"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#attr-translate">translate</a></code> attribute gives a hint to
translators whether the content should be translated.
</ul>
<p>HTML also makes all event handler attributes from HTML4, which take the
form <code>on<var>event</var></code>, global attributes and adds
several new event handler attributes for new events it defines. For
instance, the <code class="external" title="handler-onplay"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/webappapis.html#handler-onplay">onplay</a></code>
event handler attribute for the <code class="external" title="event-media-play"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#event-media-play">play</a></code> event which is used by the API for the
media elements (<code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-video-element">video</a></code> and <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-audio-element">audio</a></code>).</p>
<h3 id="changed-elements"><span class="secno">3.3 </span>Changed Elements</h3>
<p>These elements have slightly modified meanings in HTML to
better reflect how they are used on the Web or to make them more
useful:</p>
<ul>
<!--
<li><p>The <code data-anolis-spec=html>a</code> element without an
<code data-anolis-spec=html title=attr-hyperlink-href>href</code>
attribute now represents a placeholder for where a link otherwise
might have been placed.</p></li>
html4:
Each A element defines an anchor
1. The A element's content defines the position of the anchor.
2. The name attribute names the anchor so that it may be the destination
of zero or more links (see also anchors with id).
3. The href attribute makes this anchor the source anchor of exactly one
link.
Authors may also create an A element that specifies no anchors, i.e., that
doesn't specify href, name, or id. Values for these attributes may be set
at a later time through scripts.
html:
If the a element has an href attribute, then it represents a hyperlink (a
hypertext anchor).
If the a element has no href attribute, then the element represents a
placeholder for where a link might otherwise have been placed, if it had
been relevant.
Both basically say that <a> without href is a "placeholder", so this isn't
really a change.
-->
<!--
<li><p>The <code data-anolis-spec=html>abbr</code> element now represents
an abbreviation <em>or</em> an acronym.
html4:
Indicates an abbreviated form (e.g., WWW, HTTP, URI, Mass., etc.).
html:
The abbr element represents an abbreviation or acronym, optionally with
its expansion.
Not a major change (technically acronym is a form of abbreviation anyway),
and this document says to use abbr instead of acronym already.
-->
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-address-element">address</a></code> element is now
scoped by the nearest ancestor <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-article-element">article</a></code>
or <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/sections.html#the-body-element">body</a></code> element.</li>
<!--
AREA
html4 doesn't really have a definition of area, but html does, but that's
hardly worth calling out here.
-->
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-b-element">b</a></code> element now represents a
span of text to which attention is being drawn for utilitarian purposes
without conveying any extra importance and with no implication of an
alternate voice or mood, such as key words in a document abstract, product
names in a review, actionable words in interactive text-driven software,
or an article lede.</li>
<!--
BASE
html4:
The BASE element allows authors to specify a document's base URI
explicitly.
html:
The base element allows authors to specify the document base URL for the
purposes of resolving relative URLs, and the name of the default browsing
context for the purposes of following hyperlinks. The element does not
represent any content beyond this information.
-->
<!--
BDO
html4:
The BDO element allows authors to turn off the bidirectional algorithm for
selected fragments of text.
html:
The bdo element represents explicit text directionality formatting control
for its children. It allows authors to override the Unicode bidirectional
algorithm by explicitly specifying a direction override.
-->
<!--
<li><p>The <code data-anolis-spec=html>blockquote</code> element now
represents a section that is quoted <em>from another source</em> (and that
is not necessarily "long").
html4:
These two elements designate quoted text. BLOCKQUOTE is for long
quotations (block-level content)
html:
The blockquote element represents a section that is quoted from another
source.
-->
<!--
BODY
html4:
The body of a document contains the document's content.
html:
The body element represents the main content of the document.
-->
<!--
BR
html4:
The BR element forcibly breaks (ends) the current line of text.
html:
The br element represents a line break.
-->
<!--
BUTTON
html4:
Buttons created with the BUTTON element function just like buttons created
with the INPUT element
html:
The button element represents a button.
-->
<!--
CAPTION
html4:
When present, the CAPTION element's text should describe the nature of the
table.
html:
The caption element represents the title of the table that is its parent,
if it has a parent and that is a table element.
-->
<li><p>The <code class="external"><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/text-level-semantics.html#the-cite-element">cite</a></code> element now solely
represents the title of a work (e.g. a book, a paper, an essay, a poem, a
score, a song, a script, a film, a TV show, a game, a sculpture, a
painting, a theatre production, a play, an opera, a musical, an
exhibition, a legal case report, etc). Specifically the example in HTML4
where it is used to mark up the name of a person is no longer considered
conforming.</li>
<!--
CODE
html4:
Designates a fragment of computer code.
html:
The code element represents a fragment of computer code.
-->