This document is part of a series of documents published by the W3C Web Accessibility Initiative (WAI) to support WCAG 2.0 [WCAG20]. It includes a variety of techniques which include specific authoring practices and examples for developing more accessible Web content. As well, it lists failures, which describe common mistakes that are considered failures of WCAG 2.0 Success Criteria.
This is not an introductory document. It is a detailed technical description of techniques that can be used to address the requirements in WCAG 2.0. See Web Content Accessibility Guidelines (WCAG) Overview for an introduction to WCAG, supporting technical documents, and educational material.
In order to make the set of techniques maintained by the WCAG WG as comprehensive as possible, the WCAG WG encourages submission of new techniques so they can be considered for inclusion in this document. Please submit techniques for consideration using the "Techniques Submission Form."
Rather than having technology specific techniques in WCAG 2.0, the guidelines and Success Criteria themselves have been written in a technology neutral fashion. In order to provide guidance and examples for meeting the guidelines using specific technologies (for example HTML) the working group has identified sufficient techniques for each Success Criterion that are sufficient to meet that Success Criterion. In some cases it's only when a combination of techniques are used that it is considered sufficient. In these cases, the sufficient combination of techniques are listed together on one numbered line in the “How to Meet WCAG 2.0” and “Understanding WCAG 2.0” documents. Each numbered line is sufficient to meet the Success Criteria it addresses, but the individual techniques on that line are not sufficient by themselves unless they are on a numbered line by themselves.
The list of sufficient techniques is maintained in the "Understanding WCAG 2.0" (and mirrored in How to Meet WCAG 2.0). By separating the WCAG 2 normative guidelines document from the techniques used to meet the success criteria in those guidelines it is possible to update the list as new techniques are discovered, and as Web Technologies and Assistive Technologies progress.
Note that all techniques are informative. The "sufficient techniques" are considered sufficient by the WCAG Working Group to meet the success criteria. However, it is not necessary to use these particular techniques. If techniques are used other than those listed by the Working Group, then some other method for establishing the technique's ability to meet the Success Criteria would be needed.
Most Success Criteria have multiple sufficient techniques listed. Any of the listed sufficient techniques can be used to meet the Success Criterion. There may be other techniques which are not documented by the working group that could also meet the Success Criterion. As new sufficient techniques are identified they will be added to the listing.
In addition to the sufficient techniques, there are a number of advisory techniques that can enhance accessibility, but did not qualify as sufficient techniques because they are not sufficient to meet the full requirements of the Success Criteria, they are not testable, and/or because they are good and effective techniques in some circumstances but not effective or helpful in others. These are listed as advisory techniques and are right below the sufficient techniques. Authors are encouraged to use these techniques wherever appropriate to increase accessibility of their Web pages.
Note: Code examples found in the sufficient techniques are intended to demonstrate the principle discussed in the description of the technique. The code is not intended to demonstrate other aspects of accessibility, usability or best coding practices not related to the technique.
The following list includes links to a series of techniques document collections.