What is the difference between WCAG A, AA and AAA?

Question

What is the difference between WCAG A, AA and AAA

Answer

The Conformance level is the first requirement in conforming with WCAG standards
Below are reference information provided by W3C on understanding conformance:

Conformance Level: One of the following levels of conformance is met in full.

Level A: For Level A conformance (the minimum level of conformance), the Web page satisfies all the Level A Success Criteria, or a conforming alternate version is provided.

Level AA: For Level AA conformance, the Web page satisfies all the Level A and Level AA Success Criteria, or a Level AA conforming alternate version is provided.

Level AAA: For Level AAA conformance, the Web page satisfies all the Level A, Level AA and Level AAA Success Criteria, or a Level AAA conforming alternate version is provided.

 

The levels of conformance is set by W3C on the Success Criterion level of the WCAG Standards. A reference page on How to meet WCAG 2.0 shows a quick reference on the different success criterions of WCAG 2.0 and the associated levels for each criterion.