Web Accessibility Principles and Guidelines from WCAG

We have duplicated the Web Content Accessibility Guidelines (WCAG) principles and guidelines to integrate additional resource links as they are associated to each. The primary links will lead you to the full descriptions from the W3C, while resource links are displayed below the guidelines.

WCAG Levels

In order to determine the depth that each site complies with the guidelines, they developed three grade levels (A, AA, AAA). Each of the guidelines associates its compliance to one of the levels. Level A consists of foundational guidelines that at a minimum all web sites should meet. Level AA is harder to meet than Level A, but is the defacto achievement Level required by OCR. Level AAA is much harder to achieve - on larger sites, most agree it is not likely attainable. An example comparison for the levels could be found in Color Contrast... where Level A could be a blue background with yellow text, a Level AA could be a blue background with white text, and Level AAA could be a black background with white text.

National Center on Accessible Educational Materials

The AEM site shows a pretty simplified explanation of the POUR principle.