XHTML 1.0 The Extensible HyperText Markup Language (Second Edition)

This specification defines the Second Edition of XHTML 1.0, a reformulation of HTML 4 as an XML 1.0 application, and three DTDs corresponding to the ones defined by HTML 4. The semantics of the elements and their attributes are defined in the W3C Recommendation for HTML 4. These semantics provide the foundation for future extensibility of XHTML. Compatibility with existing HTML user agents is possible by following a small set of guidelines.


Some of the benefits of migrating to XHTML in general are:

Document developers and user agent designers are constantly discovering new ways to express their ideas through new markup. In XML, it is relatively easy to introduce new elements or additional element attributes. The XHTML family is designed to accommodate these extensions through XHTML modules and techniques for developing new XHTML-conforming modules (described in the XHTML Modularization specification). These modules will permit the combination of existing and new feature sets when developing content and when designing new user agents.

Alternate ways of accessing the Internet are constantly being introduced. The XHTML family is designed with general user agent interoperability in mind. Through a new user agent and document profiling mechanism, servers, proxies, and user agents will be able to perform best effort content transformation. Ultimately, it will be possible to develop XHTML-conforming content that is usable by any XHTML-conforming user agent.

Table of Contents

  • What is XHTML?
  • Definitions
  • Normative Definition of XHTML 1.0
  • Differences with HTML 4
  • Compatibility Issues
  • DTDs
  • Element Prohibitions
  • HTML Compatibility Guidelines
  • Acknowledgements
  • References

Book Details

Author(s): Members of the W3C HTML Working Group.
Format(s): PDF, HTML, PostScript
File size: 113 KB
Number of pages: 32
Link: Download or read online.

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