W3C home page Web Accessibility Initiative (WAI) home page

Overview of Notes on Accessibility Features of W3C Technologies

Version: 0.2 (Early Rough Draft 2004.07.25)
Note: This Web page is a working draft and should not be referenced or quoted under any circumstances.

Accessibility of W3C Technologies
Cascading Style Sheets
Synchronised Multimedia Integration Language
Scalable Vector Graphics
HTML 4.0
Notes format
Who develops these Notes
Accessibility Features of Cascading Style Sheets (CSS) (W3C Note, 4 August 1999)
Accessibility Features of Synchronized Multimedia Integration Language (SMIL) (W3C Note, 21 September 1999)
Accessibility Features of Scalable Vector Graphics (SVG) (W3C Note, 7 August 2000)
Accessibility Improvements in HTML 4.0 (WAI Resouce, 8 November 2000)

Accessibility of W3C Technologies

One of W3C's primary goals is to make the Web and its communication and interaction benefits available to all people, whatever their hardware, software, network infrastructure, native language, culture, geographical location, or physical or mental ability. Thus, accessibility is taken into account in the development of all W3C technologies, and a series of Notes have been prepared to document these features.WAI has also developed a series of accessibility guidelines - listed in Guidelines and Techniques page. The relationship between the different guidelines is explained in the Components of Web Accessibility page.

Developers of web pages and applications, graphics, and multimedia, should integrate the accessibility features of W3C technologies, and follow the appropriate guidelines, in their developments to benefit users with visual, auditory, motor and/or cognitive disabilities.

Accessibility Features of CSS

Cascading STyle Sheets (CSS) benefit accessibility primarily by separating document structure from presentation. Style sheets were designed to allow precise control - outside of markup - of character spacing, text alignment, object position on the page, audio and speech output, font characteristics, etc. By separating style from markup, authors can simplify and clean up the HTML in their documents, making the documents more accessible at the same time. Many CSS features directly affect the accessibility of Web documents. This Note summarizes the accessibility features of the Cascading Style Sheets (CSS), level 2 Recommendation. Some of the accessibility features described in the Note were available in CSS1 as well.

Specific CSS2 feature that benefit accessibility include:

The W3C has also released a Techniques document describing CSS Techniques for Web Content Accessibility Guidelines 1.0.

Accessibility Features of SMIL

Multimedia presentations rich in text, audio, video, and graphics are becoming more and more common on the Web. They include newscasts, educational material, entertainment, etc. Formats such as SMIL can be used to create dynamic multimedia presentations by synchronizing the various media elements in time and space. Authors can make SMIL presentations accessible to people with disabilities by observing the principles discussed in the "Web Content Accessibility Guidelines 1.0". This Note applies the principles of the Web Content Accessibility Guidelines to SMIL 1.0 and explains which SMIL 1.0 features will help you create accessible presentations.

This Note summarizes the accessibility features of the Synchronized Multimedia Language (SMIL), version 1.0 Recommendation.

Accessibility Features of SVG

Scalable Vector Graphics (SVG) is an Extensible Markup Language (XML) application for producing Web graphics. SVG offers a number of features to make graphics on the Web more accessible than is currently possible with other graphics formats and to a wider group of users. Users who benefit include users with low vision, blindness, or color blindness, and other users of assistive technologies. A number of these SVG features can also increase usability of content for many users without disabilities, such as users of personal digital assistants, mobile phones or other non-traditional Web access devices.

This Note discusses the accessibility features of the Scalable Vector Graphics (SVG) 1.0 Specification; these features are equally applicable to the SVG 1.1 Specification.

HTML 4.0 Accessibility Improvements

The Web Accessibility Initiative (WAI), joined forces with the W3C HTML Working Group in the design of HTML 4.0, which became a W3C Recommendation in December, 1997. For this release of the World Wide Web's publishing language, the WAI group sought remedies for a number of authoring habits that cause problems for users with screen readers, audio browsers, and text-only browsers. In particular the Resource addresses the issues of structured documents, style sheets, alternative content, and navigation and orientation.

This Resource describes how certain aspects of the HTML 4.0 Specification (in conjunction with style sheets) allow authors to avoid accessibility pitfalls. These aspects are also available in HTML 4.01 and @@XHTML Vx.x.

The W3C has also released a Techniques document describing HTML Techniques for Web Content Accessibility Guidelines 1.0.

Note format

The Notes in this document follow the W3C format for Notes. W3C Notes include at the beginning: version links, editors, copyright, abstract, status, and table of contents.

Who develops these Notes

WAI Notes are developed by working groups in the World Wide Web Consortium (W3C) Web Accessibility Initiative (WAI). The W3C Note development process includes formal periods for public review. Opportunities for review of WAI documents are announced on the W3C home page, WAI home page, and WAI Interest Group mailing list. Other opportunities for contributing are listed in Participating in WAI.

Document Information

Editor: Andrew Arch. Last updated $Date: 2004/07/27 02:18:30 $ by $Author: andrewa $

Copyright © 1994-2004 W3C ® (MIT, ERCIM, Keio), All Rights Reserved. W3C liability, trademark, document use and software licensing rules apply. Your interactions with this site are in accordance with our public and Member privacy statements.