XHTML2 Working Group Roadmap

Steven Pemberton, HTML Activity Lead and Working Group Chair, W3C/CWI
Roland Merrick, Working Group Chair, IBM
Last modified:
$Date: 2008/11/26 16:36:18 $


This document describes the time line for deliverables of the XHTML2 Working Group. It will be updated from time to time.

Status of this document

This document describes the plans of the XHTML2 Working Group for each of its deliverables. While those plans may change, they represent the group's best guess as of the date on this document. This document may be updated, replaced or rendered obsolete by other W3C documents at any time. It is inappropriate to use this document as reference material or to cite them as other than "work in progress". This document does not imply endorsement by the W3C Membership.

This document has been produced as part of the W3C HTML Activity. The goals of the XHTML2 Working Group are discussed in the XHTML2 Working Group Charter.

Table of Contents

1. Introduction

The XHTML2 Working Group is chartered with the development of an extensible, sub-settable version of HTML that is compatible with XML, now known as XHTML. It is also chartered with the development of some extensions, such as a new event mechanism. The group was chartered in March 2007. The purpose of this document is to describe the activities of the Working Group, define general milestones for each sub-project, and outline the inter-dependencies among the various deliverables.

This document reflects the project plan of the XHTML2 Working Group. As such, it is a living document subject to change without notice.

2. Working Group Goals

The Working Group's goals can be summarized as follows:

2.1. Modularization of XHTML

Modularizing XHTML makes the management of profiles and embeddings easier. For resource constrained devices for instance, it may be impractical to support all of XHTML. Subsets of XHTML are limited to combining selected XHTML modules, and once a module has been chosen, all of its features must be supported. XHTML 1.1 provides an example of how to combine XHTML modules. The modules have been formalized using XML 1.0 DTDs, and further work is underway on recasting them with XML schemas.

2.2. Next Generation of XHTML

XHTML development involves developing a next generation markup language, namely XHTML 2.0. The design goal of XHTML 2.0 is to use XML-generic technologies as much as possible. In this version the Working Group will clean up legacy features, and redesign them where appropriate.

2.3. Related deliverables

Some features are being developed separately from XHTML, such as a generalized event mechanism, replacement for Frames and so on.

2.4. Combining XHTML with other XML vocabularies

W3C's work on areas such as math, scalable vector graphics, synchronized multimedia, voice browsing and forms holds great promise for a new generation of Web content. Modularization of XHTML has made it possible to combine these vocabularies with XHTML. The Working Group will collaborate with other Working Groups to define profiles for combining XHTML with other vocabularies.

3. Development Schedule

The general development plan is described in the following table. The dates show are actual (past) or projected (future) dates when each document enters the given phase in its process. Completion of that phase is subject to W3C procedures.

Maintenance mode
Deliverable 1st draft 2nd draft Last Call ends CR PR REC 2nd Ed. 3rd Ed.
XHTML 1.0 5 Dec 1998 24 Feb 1999 4 Mar 1999 24 Mar 1999 - 24 Aug 1999 26 Jan 2000 1 Aug 2002 TBD
5 May 1999 1 Jun 1999 10 Dec 1999
Modularization 1.0 6 Apr 1999 10 Sep 1999 5 Jan 2000 1 Feb 2000 20 Oct 2000 22 Feb 2001 10 Apr 2001
XHTML 1.1 10 Sep 1999 - 5 Jan 2000 1 Feb 2000 - 6 Apr 2001 31 May 2001


XHTML Basic 1.0 21 Dec 1999 - 10 Feb 2000 15 Mar 2000 - 3 Nov 2000 19 Dec 2000
XML Events 21 Dec 1999 28 Aug 2000 26 Oct 2001 30 Nov 2001 7 Feb 2003 4 Aug 2003 14 Oct 2003 TBD -
XHTML-Print 29 July 2003 - 29 July 2003 7 Sep 2003 20 Jan 2004 31 Jan 2006 20 Sep 2006


Media Type 18 Dec 2000 8 Feb 2001 27 Sep 2001 26 Oct 2001 - - 6 Feb 2002 TBD -
Modularization of XHTML in XML Schema 22 Mar 2001 19 Dec 2001 9 Dec 2002 31 Jan 2003 Replaced by Modularization 1.1
3 Oct 2003 14 November 2003
New and continuing
Deliverable 1st draft Latest draft Last Call ends CR PR REC 2nd Ed. 3rd Ed.
Access module 7 Jan 2008 26 May 2008 16 June 2008 Dec 2008
XFrames 6 Aug 2002 12 Oct 2005 Sep 2008 - -
XML Events 2 16 Feb 2007 - Dec 2008 - -
XHTML 2.0 5 Aug 2002 26 July 2006 2009-03 2009-06 2009-12 2010-03
XHTML Basic 1.1 7 June 2006 - 5 July 2006 4 Aug 2006 13 July 2007 11 June 2008 29 July 2008 - -
RDFa Primer 12 Mar 2007 Feb 2008 (as note)
RDFa module replaced by RDFa in XHTML: Syntax and Processing
RDFa in XHTML: Syntax 18 Oct 2007 21 Feb 2008 25 Mar 2008 20 June 2008 4 Sept 2008 14 Oct 2008
RDFa Use Cases 30 Mar 2007
Modularization 1.1 13 Feb 2006 - 5 July 2006 4 Aug 2006 - 11 June 2008 8 Oct 2008 - -
Modularization 2 2008 - -
XHTML Role Attribute Module 25 July 2006 13 Nov 2006 04 Oct 2007 26 Oct 2007
7 Apr 2008 10 May 2008 Dec 2008 - - -
CURIE Syntax 07 Mar 2007 2 Apr 2008 5 May 2008 10 June 2008 Dec 2008 - - -

Each of these deliverables is described in the following sections.

4. Working Group Deliverables

4.1. XHTML Access Module

Latest Drafts of XHTML Access Module

This deliverable satisfies the Working Group Charter deliverable "Accesskey module".

The XHTML Access module defines an element that, when used in conjunction with other XHTML modules, enables a more robust accessibility model.

4.2. XFrames

Editor: Steven Pemberton, W3C/CWI

Latest Draft

This document defines XFrames, a new XML Application for composing documents together into a single view, to replace HTML Frames with similar functionality but with fewer usability problems.

XFrames is an independent XML vocabulary, and doesn't belong to XHTML.

4.3. XML Events 2

Latest Drafts of XML Events 2

The XML Events 2 module provides XML languages with the ability to uniformly integrate event listeners and associated event handlers with Document Object Model (DOM) Level 2 event interfaces.

4.4. XHTML 2.0

Editors: Shane McCarron, ApTest et al.

Latest Draft

XHTML 2.0 is a next generation markup language. In this version, the functionality is expected to remain similar to (or a superset of) that of XHTML 1.1. However, the markup language may be altered semantically and syntactically to conform to the requirements of related XML standards such as XML Base and XML Schema. The objective of these changes is to ensure that XHTML 2.0 can be readily supported by XML browsers that have no arcane knowledge of XHTML semantics such as linking, image maps, forms, etc. The development of XHTML 2.0 will likely require the development of new XHTML modules or revisions to existing XHTML modules.

4.5. XHTML Basic 1.1

Latest Drafts of XHTML Basic 1.1

XHTML Basic is a simplified yet forward-looking markup language built using modules defined in XHTML Modularization. This revision, 1.1, supercedes version 1.0. In this revision, several new features have been incorporated into the language in order to better serve the small-device community that is this language's major user.

4.6. RDFa

Latest Drafts of RDFa in XHTML: Syntax and Processing

The Working Group Charter includes a deliverable "RDFa module". This deliverable is now entitled "RDFa in XHTML: Syntax and Processing".

The RDFa documents are produced jointly by the Semantic Web Deployment Working Group and the XHTML 2 Working Group. Additional documents on the subject of RDFa are also available: RDFa Use Cases: Scenarios for Embedding RDF in HTML and RDFa Primer.

Current web pages, written in HTML, contain significant inherent structured data. When publishers can express this data more completely, and when tools can read it, a new world of user functionality becomes available, letting users transfer structured data between applications and web sites. An event on a web page can be directly imported into a user's desktop calendar. A license on a document can be detected so that the user is informed of his rights automatically. A photo's creator, camera setting information, resolution, and topic can be published as easily as the original photo itself, enabling structured search and sharing.

RDFa is a syntax for expressing this structured data in XHTML. The rendered, hypertext data of XHTML is reused by the RDFa markup, so that publishers don't repeat themselves. The underlying abstract representation is RDF, which lets publishers build their own vocabulary, extend others, and evolve their vocabulary with maximal interoperability over time. The expressed structure is closely tied to the data, so that rendered data can be copied and pasted along with its relevant structure.

4.7. Modularization 1.1

Latest Drafts of XHTML™ Modularization 1.1

XHTML Modularization 1.1 specifies an XML Schema version in addition to the XML Document Type Definitions (DTDs) specified in the Modularization of XHTML™ 1.0 Recommendation. It builds on and superceeds an earlier "Modularization of XHTML 1.0 - Second Edition" Working Draft as well as "XHTML™ 1.0 in XML Schema" W3C Note

4.8. XHTML Role Attribute Module

Latest Drafts

The XHTML Role Attribute an author to annotate XML Languages with machine-extractable semantic information about the purpose of an element. Use cases include accessibility, device adaptation, server-side processing, and complex data description.

4.9. CURIE Syntax

Latest Drafts

CURIE Syntax defines a syntax for expressing URIs in a generic, abbreviated syntax.

4.10. Test Suites

The Working Group will develop test suites for each Recommendation-track specification.

4.11. Maintenance of published Recommendations

The Working Group has successfully published the following Recommendations. The Working Group will maintain errata for them, and will publish new editions when appropriate.

4.11.1. XHTML 1.0 - Extensible HTML

Editors: Steven Pemberton, W3C/CWI et al.


XHTML 1.0 is a definition of traditional HTML 4 expressed in three XML DTDs. It also defines conformance requirements for XHTML 1.0 documents and user agents. Finally, it provides guidelines for developing XHTML 1.0 conforming content that will operate in today's HTML user agents.

This specification forms the basis for a family of document types and modules that will collectively be known as "XHTML". It is targeted at content developers who want to be forward looking and backward compatible, and also at user agent developers who want to start making the transition from SGML to XML.

4.11.2. XHTML Modularization


A Second Edition (Working Draft) was published but has been superceeded by Modularization 1.1.

XHTML Modularization defines a collection of abstract modules that can be grouped together and used as the basis for future document type definitions. It also defines a framework for defining additional abstract modules and their implementations via XML DTDs. Finally, it provides an implementation of these modules using XML DTDs, and then uses that implementation as components to reconstruct the XHTML 1.0 DTDs and some additional DTDs as examples.

This specification is targeted at client developers who wish to augment the basic definitions of XHTML with additional client-specific markup. It is also useful for content developers who wish to extend XHTML with document-specific markup. Finally, it is extremely useful for other standards groups (both within and outside of the W3C) who are designing new markup that should be combinable with XHTML.

4.11.3. XHTML 1.1

Editors: Shane McCarron, ApTest et al.


XHTML 1.1 is a forward-looking markup language built using modules defined in XHTML Modularization. The purpose of XHTML 1.1 is to serve as the basis for future extended XHTML 'family' document types, and to provide a consistent, forward-looking document type cleanly separated from the deprecated, legacy functionality of XHTML 1.0 (and from HTML 4). XHTML 1.1 is essentially a reformulation of XHTML 1.0 Strict using XHTML Modules, plus ruby.

4.11.4. XHTML Basic

Editors: Peter Stark, Sony Ericsson et al.


XHTML Basic is a simplified yet forward-looking markup language built using modules defined in XHTML Modularization. It is intended for use as the basis of other markup languages targeted at thin clients, such as those being produced by the television and wireless communities.

4.11.5. XML Events

Editors: Shane McCarron, Applied Testing and Technology, Inc., Steven Pemberton, W3C/CWI, and T. V. Raman, IBM


This specification provides XML languages with the ability to uniformly integrate event listeners and associated event handlers with DOM Level 2 event interfaces. The result is to provide an interoperable way of associating behaviors with document-level markup.

4.11.6. XHTML-Print

Editor: Jim Bigelow, Hewlett-Packard


XHTML-Print is member of the family of XHTML languages defined by the Modularization of XHTML. It is designed to be appropriate for printing from mobile divices to low-cost printers that may not have a full-page buffer and that generally print from top-to-bottom and left-to-right with the paper in a portrait orientation.

XHTML-Print has its origin in the XHTML-Print defined by the Printer Working Group, a group chartered to make printers and the applications and operating systems supporting them work together better.

5. Finished Work Items

Work on the following work items are basically finished, and new development is not planned for them.

5.1. Media Type for XHTML

Editors: Mark Baker, Planetfred, Inc. and Peter Stark, Sony Ericsson

RFC 3236

This document defines the 'application/xhtml+xml' MIME media type for XHTML based markup languages; it is not intended to obsolete any previous IETF documents, in particular RFC 2854 which registers 'text/html'. The XHTML Media Types Note summarizes how to use various media types for serving various XHTML Family documents.

5.2. XML Schemas for XHTML

Editor: Masayasu Ishikawa, W3C

XHTML™ 1.0 in XML Schema: W3C Note

"Modularization of XHTML in XML Schema" describes a modularization framework for languages within the XHTML namespace using XML Schema. This document provides a complete set of XML Schema modules for XHTML. In addition to the schema modules themselves, the framework presented here describes a means of further extending and modifying XHTML. XML Schemas for XHTML 1.0, XHTML 1.1 and XHTML Basic will also be provided.

5.3. An XHTML + MathML + SVG Profile

Editor: Masayasu Ishikawa, W3C

Latest Draft

An XHTML+MathML+SVG profile is a profile that combines XHTML 1.1, MathML 2.0 and SVG 1.1 together. This profile enables mixing XHTML, MathML and SVG in the same document using XML namespaces mechanism, while allowing validation of such a mixed-namespace document.

This specification is a joint work with the SVG Working Group, with the help from the Math WG.

6. Transferred Work Items

The following work items were formerly dealt by the HTML Working Group, but have been transferred to other Working Groups for further development and those are not covered by the current HTML Working Group Charter anymore.

6.1. Next Generation Forms

Work on the next generation of Web forms has now been handed over to the XForms Working Group. For more information please refer to the XForms overview page.

Published document:
XHTML Extended Forms Requirements, 6 September 1999

6.2. Document Profiles

Work on document profile has been transferred to the Device Independence Working Group. For more information please refer to the Device Independence Working Group Charter.

Published document:
XHTML Document Profile Requirements, 6 September 1999

6.3. XHTML + SMIL Profile

With the creation of the new Synchronized Multimedia Working Group (SYMM WG), this work item has been put back to the SYMM WG again.

Published document:
XHTML+SMIL Profile, 31 January 2002