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WAI: Strategies, guidelines, resources to make the Web accessible to people with disabilities

Overview of WCAG 2.0 Documents

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An acronym for the WCAG 2.0 principles is POUR:

  • Perceivable
  • Operable
  • Understandable
  • Robust

WCAG 2.0 Last Call Status

On 27 April 2006 WAI issued a "Last Call" for the main WCAG 2.0 Working Draft document. Please see the Extending Deadline on WCAG 2.0 Last Call Review e-mail that encourages review and comment by 22 June 2006.

Last Call means that the WCAG Working Group believes that WCAG 2.0 Working Draft addresses all substantial issues, satisfies technical requirements, and is stable. WCAG 2.0 will go through two more stages before it is completed as a "W3C Recommendation" or standard: Candidate Recommendation and Proposed Recommendation. "Advancing a Technical Report to Recommendation" in the W3C Process Document describes these stages.

The time between this Last Call and final publication as a W3C Recommendation will be at least 6 months, and may be more. Because of the nature of the W3C specification development process, WAI cannot be certain when the final version of WCAG 2.0 will be available. WCAG 1.0 will remain the latest approved version until WCAG 2.0 is complete.

Introduction

This page introduces the WCAG 2.0 Working Draft documents as of April 2006, and highlights how WCAG 2.0 working drafts differ from WCAG 1.0.

For general information about Web Content Accessibility Guidelines (WCAG) and WCAG 1.0, see Web Content Accessibility Guidelines (WCAG) Overview.

Web Content Accessibility Guidelines 1.0 was approved in May 1999 and is the stable and referenceable version. WCAG 2.0 documents are being developed to apply to more advanced Web technologies, be easier to use and understand, and be more precisely testable, as documented in Requirements for WCAG 2.0.

WCAG 2.0 Working Draft Documents

The WCAG 2.0 documents include:

The main WCAG 2.0 document is on the W3C Recommendation Track to become a W3C Recommendation, or standard. The other supporting documents will be W3C Notes or WAI resources.

WCAG 2.0

The WCAG 2.0 Working Draft is organized around four design principles for Web accessibility:

  1. Content must be perceivable
  2. Interface elements in the content must be operable
  3. Content and controls must be understandable
  4. Content should be robust enough to work with current and future Web technologies

Under each principle are guidelines that define how the principle applies in a specific area.

Under each guideline are success criteria. Success criteria are testable statements to further define the guideline and to determine conformance. The success criteria are also available in a WCAG 2.0 Working Draft appendix: Checklist for WCAG 2.0.

Understanding WCAG 2.0

Understanding WCAG 2.0 is a guide to learning and implementing WCAG 2.0. It provides extensive guidance to help understand the intent of each guideline and success criteria, and it lists techniques to meet each success criteria.

Understanding WCAG 2.0 includes the following information about each success criterion:

Understanding WCAG 2.0 will be the primary document that many people use to learn and apply WCAG 2.0, as it lists each guideline and success criterion from WCAG 2.0 along with the additional information described above.

Techniques for WCAG 2.0

Techniques for WCAG 2.0 provide specific details on ways ("techniques") to develop accessible Web pages. The Techniques for WCAG 2.0 document is a collection of techniques, which each include a description, examples, code, notes on user agent and assistive technology support, and tests.

The document includes sections on: General Techniques (that apply to all Web content and are not specific to any one technology); HTML Techniques; CSS Techniques; Client-side Scripting Techniques; Server Side Techniques; SMIL Techniques; Plain Text Techniques; and Common Failures (mistakes made by authors).

WCAG 2.0 Quick Reference

WCAG 2.0 Quick Reference lists requirements (success criteria) and techniques to meet WCAG 2.0. You can customize it to list the success criteria levels and Web technologies that you are using.

About Baselines for WCAG 2.0

About Baselines for WCAG 2.0 explains a new concept in WCAG 2.0: a technology baseline. A baseline is the set of technologies that an author assumes are supported and turned on in user agents and assistive technologies. Baselines are related to conformance claims. When a Web site claims to conform to WCAG 2.0, all information and functionality of the Web content conform to WCAG 2.0 even when a user agent supports only the technologies in the baseline.

Application Notes

In the future, “Application Notes” (working title) may be provided in conjunction with WCAG 2.0. Application Notes would provide detailed guidance for a specific topic, such as images, links, or tables. For example, an Application Note on forms would include WCAG 2.0 success criteria, techniques, and strategies for developing accessible forms.

Navigating WCAG 2.0 Documents

The main WCAG 2.0 document is currently divided into the following 9 Web pages:

All of the information above is also available on one Web page, which is useful for printing or downloading as a single HTML file.

The Understanding WCAG 2.0 document is currently one large Web page, as is the Techniques for WCAG 2.0 document. In the future, these documents may be broken up into multiple pages (where each “How To” section of Understanding WCAG 2.0 and each technique is its own page).

Throughout the WCAG 2.0 documents are links to related information in other documents. For example, from WCAG 2.0 a link such as "How to meet 1.1.1" goes to a section within Understanding WCAG 2.0 that describes how to meet that success criterion and lists techniques. The techniques lists are links that go to the detailed description of the technique within Techniques for WCAG 2.0.

How WCAG 2.0 Working Drafts Differ from WCAG 1.0

WCAG 2.0 Working Draft guidelines and success criteria are more robust, technology-independent and testable, and the WCAG 2.0 supporting documents include more information than was provided with WCAG 1.0.

In WCAG 1.0, a brief descriptions of issues are included in the main WCAG 1.0 document under each guideline. With WCAG 2.0, extensive guidance is provided in Understanding WCAG 2.0, as explained above.

WCAG 1.0 Priority Checkpoints versus WCAG 2.0 Level Success Criteria

WCAG 1.0 is organized around guidelines that have checkpoints, which are priority 1, 2, or 3. The basis for determining conformance to the WCAG 1.0 are the checkpoints.

WCAG 2.0 is organized around four design principles of Web accessibility. Each principle has guidelines, and each guideline has success criteria at level 1, 2, or 3. The basis for determining conformance to the WCAG 2.0 Working Draft are the success criteria.

Differences in Techniques Documents

The Techniques for WCAG 1.0 document, sometimes called the "Techniques Gateway", provides only links to relevant technology-specific techniques documents, as explained in Navigating WCAG 1.0 Guidelines and Techniques Documents. A separate document, Core Techniques for WCAG 1.0, provides general techniques, and there are two technology-specific techniques documents covering HTML and CSS.

1.0 checkpoint <links to> "Gateway" Techniques <links to> technique

The Techniques for WCAG 2.0 are much more robust and complete than those for WCAG 1.0, as described in the "Techniques" section above. The Techniques for WCAG 2.0 document currently includes general techniques and technology-specific techniques. Techniques are linked from the Understanding WCAG 2.0 document.

2.0 success criteria <links to> "How to Meet" in Understanding <links to> technique

Transitioning from WCAG 1.0 to WCAG 2.0

Comparison of WCAG 1.0 Checkpoints to WCAG 2.0 shows the relationship between WCAG 1.0 checkpoints and WCAG 2.0.

Most Web sites that conform to WCAG 1.0 should not require significant changes in order to conform to WCAG 2.0, and may not need any changes. WAI will provide additional resources to help organizations that are currently using WCAG 1.0 to transition to WCAG 2.0.