Guidelines and Standards
The information presented in Accessible Design is written with the guidelines in mind, but does not go into detail about how and why they are used. Following is a brief introduction to the guidelines and standards that have been created for accessible web design. All web designers should read and have a basic understanding of them. However, be aware that that the guidelines and standards can at times be unnecessarily strict when it comes to accessibility. Contained within them are generalities that don't always work in every case. For example, one guideline mentions needing to provide a method to skip over lists of links; however, this wouldn't apply to a resource page with a long list of links.
WCAG 1.0
The WCAG 1.0, created by the Web Accessibility Initiative (WAI) of the World Wide Web Consortium (W3C), became the official Recommendation of the W3C on May 5, 1999. It consists of 14 guidelines, each one including a set of checklists that explain how the guideline applies to Web development.
For more information, see the WCAG 1.0 Documents (offsite link) at W3C.org.
WCAG 2.0
WCAG 1.0 is undergoing revision. While still in draft form as of April 2008, the W3C encourages web designers to use version 2.0 rather than awaiting the final version. Like version 1.0, version 2.0 is organized around guidelines. There are 13 guidelines, each containing a list of items similar to checkpoints.
There are two major differences between versions 1.0 and 2.0: First, the checkpoints have been changed to "success criteria," which are testable statements of what needs to be done to satisfy each guideline. The wording of the guidelines/success criteria has been changed to more general statements, in order to be technology independent. Second, success criteria under each guideline are not prioritized by their importance or priority. Instead, they are ranked by the extent to which the web design and development process must be modified in order to meet each success criterion.
For more information, see the WCAG 2.0 Documents (offsite link) at W3C.org.
Section 508 Standards
The U.S. Access Board issued access standards for federal electronic and information technology as required under Section 508 of the Rehabilitation Act. All electronic and information technology purchased by the U.S. federal government must comply with these provisions. Many provisions correspond to Priority 1 WCAG checkpoints with minor changes for regulatory wording. Some of the Priority 1 checkpoints were deemed to by the Access Board to be too restrictive on web development, or too difficult to judge for compliance. In addition, Section 508 Standards add provisions that combine the checkpoints of lower priority.
For more information, see the official site for Section 508 Standards (offsite link).