Web Content Accessibility Guidelines (WCAG 2.1)
The Web Content Accessibility Guidelines, currently in version 2.1, describe accessibility requirements for web content and web applications, but also apply to online documents and other web-based formats.
WCAG has three different conformance levels:
- The most essential requirements are placed on level A (single A)
- Oher important requirements on level AA (double A)
- Additional requirements for particular user groups that may not always be easy to meet are placed at level AAA (triple A)
In Europe and in many countries outside Europe, WCAG on level AA (which includes level A) are the basis for national accessibility laws and regulations.
Many of these laws and regulations are being revised to include the new WCAG Success Criteria of WCAG 2.1 — twelve of them on level A or AA.