On December 11th, 2008, after 5 years of working, the W3C WAI released the WCAG 2.0 . They are an evolution of the WCAG 1.0, released on May 5th, 1999, that became a little bit obsolete due to technological advances. Despite this obsolescence, many laws still standed on these guidelines, so a new version was needed.
WCAG 2 follows the spirit of trying to bring a most accessible Web, but with some changes with the previous ones.
How are ‘WCAG 2’ organized?
WCAG 2 are organized by 4 layers: principles, guidelines, success criteria and techniques to accomplish them.
- They provide the basis for Web accessibility: the website must be perceivable, operable, understandable, and robust.
- There are 12 guidelines under the principles, similar to that on the WCAG 1, but with no levels of conformance
- Success Criteria
- Each guideline has a testable success criteria. Here they are the 3 levels of conformance, equal to that on WCAG 1: A (lowest), AA, and AAA (highest).
- Each guideline and success criteria has itw own informative techniques. There are 2 categories plus sufficient techniques and the advisory ones that address. The WAI had also documented some common failures, so we can learn how to avoid them.