The HTTP / 1. 1 header specification for a HTML document must label an appropriate encoding in the Content-Type header, missing < tt > charset =</ tt > parameter results in acceptance of ISO-8859-1 ( so HTTP / 1. 1 formally does not offer such option as an unspecified character encoding ), and this specification supersedes all HTML ( or XHTML ) meta element ones.

<! DOCTYPE html PUBLIC "-// W3C // DTD XHTML 1. 0 Transitional // EN "

<! DOCTYPE html PUBLIC "-// W3C // DTD XHTML 1. 0 Transitional // EN "

XHTML is a separate language that began as a reformulation of HTML 4. 01 using XML 1. 0.

* XHTML 1. 1, published May 31, 2001, as a W3C Recommendation.

It is based on XHTML 1. 0 Strict, but includes minor changes, can be customized, is reformulated using modules from Modularization of XHTML, which was published April 10, 2001, as a W3C Recommendation.

XHTML 2. 0 was incompatible with XHTML 1. x and, therefore, would be more accurately characterized as an XHTML-inspired new language than an update to XHTML 1. x.

* XHTML5, which is an update to XHTML 1. x, is being defined alongside HTML5 in the HTML5 draft.

* XHTML 1. 0

Firefox implements many web standards, including HTML4 ( partial HTML5 ), XML, XHTML, MathML, SVG 1. 1 ( partial ), CSS ( with extensions ), ECMAScript ( JavaScript ), DOM, XSLT, XPath, and APNG ( Animated PNG ) images with alpha transparency.

;< span id =" XHTML10 "> XHTML 1. 0 :</ span >

;< span id =" XHTML11 "> XHTML 1. 1 :</ span >

XHTML, which is an XML application, supports the HTML entity set, along with XML's predefined entities.

However, use of in XHTML should generally be avoided for compatibility reasons.

The Document Object Model ( DOM ) is a cross-platform and language-independent convention for representing and interacting with objects in HTML, XHTML and XML documents.

Development of the parallel, XML-based language XHTML occupied the W3C's HTML Working Group through the early and mid-2000s.

* XHTML 2. 0 was a working draft, but work on it was abandoned in 2009 in favor of work on HTML5 and XHTML5.

It was an attempt at bridging WML and XHTML Basic before the WAP 2. 0 spec was finalized.

In the end, XHTML Mobile Profile became the markup language used in WAP 2. 0.

In computing, Resource Directory Description Language ( RDDL ) is an extension of XHTML Basic 1. 0.

The spec is based around a modularized version of XHTML 1. 1, and also includes CSS 2. 0, DOM 2. 0, and ECMAScript.

* HTML 4. 01 and XHTML 1. 0

The mobile browser usually connects via cellular network, or increasingly via Wireless LAN, using standard HTTP over TCP / IP and displays web pages written in HTML, XHTML Mobile Profile ( WAP 2. 0 ), or WML ( which evolved from HDML ).

WAP 2. 0 specifies XHTML Mobile Profile plus WAP CSS, subsets of the W3C's standard XHTML and CSS with minor mobile extensions.

* XHTML 1. 0 Support

These rich text strings are XML documents that conform to the rich text conventions specified for the XML Forms Architecture specification, which is itself a subset of the XHTML 1. 0 specification, augmented with a restricted set of CSS2 style attributes.

* WAP 2. 0 / XHTML browser ; the Internet icon appears when the phone is connected to the Web, using WAP or the built-in GPRS modem

The phone is equipped with a 128x128 pixel passive colour display ( 4096 colors / 12-bit ), Java MIDP 1. 0, XHTML and WAP browser, GPRS, Pop-Port connectivity and Lithium-ion battery.

As a semantic language, DocBook enables its users to create document content in a presentation-neutral form that captures the logical structure of the content ; that content can then be published in a variety of formats, including HTML, XHTML, EPUB, PDF, man pages, Web help and HTML Help, without requiring users to make any changes to the source.

Since January 2000 all W3C Recommendations for HTML have been based on XML rather than SGML, using the abbreviation XHTML ( Extensible HyperText Markup Language ).

* HTML / XHTML — markup language for web pages ( ISO / IEC 15445: 2000 )

During his time at Microsoft he also served as their alternate representative ( 1998 – 2000 ) and later their representative ( 2001 – 2004 ) to a number of working groups at the World Wide Web Consortium ( W3C ); he is credited on a number of recommendations relating to XHTML and Cascading Style Sheets due to this work.

* Hypertext Markup Language ( HTML ), Extensible HTML ( XHTML ) and HTML5 ( specifications of the W3C for structured hyperlinked document formatting )

:< code ><! DOCTYPE html PUBLIC "-// W3C // DTD XHTML Basic 1. 1 // EN ""< nowiki > http :// www. w3. org / TR / xhtml-basic / xhtml-basic11. dtd "</ nowiki >></ code >

<! DOCTYPE html PUBLIC "-// W3C // DTD XHTML Basic 1. 1 // EN "

XHTML-Print, which became a W3C Recommendation in September 2006, is a specialized version of XHTML Basic designed for documents printed from information appliances to low-end printers.

* W3C Mobile Web Best Practices ( for XHTML Basic 1. 1 )

* Recommendations for markup languages, such as Hypertext Markup Language ( HTML ), Extensible Hypertext Markup Language ( XHTML ), Scalable Vector Graphics ( SVG ), and XForms, from W3C.

The Markup Validation Service is a validator by the World Wide Web Consortium ( W3C ) that allows Internet users to check HTML and XHTML documents for well-formed markup.

W3C also offers validation tools for web technologies other than HTML / XHTML, such as CSS, XML schemas, and MathML.

While the W3C and other HTML and XHTML validators will assess pages coded in those formats, a separate validator like the W3C CSS validator is needed to confirm that there are no errors in the associated Cascading Style Sheet.

For example, the FPI for XHTML 1. 1 is "-// W3C // DTD XHTML 1. 1 // EN " and, there are 3 possible system identifiers available for XHTML 1. 1 depending on the needs, one of them is the URI reference " http :// www. w3. org / TR / xhtml1 / DTD / xhtml1-transitional. dtd ".

* W3C compliant XHTML 1. 0 transitional and CSS.

After the standardization of ECMAScript, W3C began work on the standardization of Document Object Model ( DOM ), which is a way of representing and interacting with objects in HTML, XHTML and XML documents.

<! DOCTYPE html PUBLIC "-// W3C // DTD XHTML 1. 0 Transitional // EN "

X + V is currently under consideration by the W3C and combines several W3C Recommendations including XHTML for visual markup, VoiceXML for voice markup, and XML Events, a standard for integrating XML languages.