Web Accessibility Standards
Web Content Accessibility Guidelines (WCAG) have been developed by the Web Accessibility Initiative (WAI) of the World Wide Web Consortium (W3C). These guidelines are most-widely accepted standards of the web accessibility. Websites should be designed and developed in compliance with these guidelines to ensure accessibility. Many countries in the world have laws that may prosecute non-compliant websites.
WCAG 2.1
WCAG 2.1 were published on 5 June 2018. These guidelines aim to improve accessibility guidance for three major groups: users with cognitive or learning disabilities, users with low vision, and users with disabilities on mobile devices. WCAG 2.1 propose 13 guidelines under the original four POUR principles.
WCAG 2.1 are fully backward compatible with the WCAG 2.0 guidelines and have 17 additional criteria (i.e. 78 total criteria).
WCAG 2.0
The WCAG 2.0 were published as a W3C Recommendation on 11 December 2008. These recommendations have a set of 12 guidelines clustered under four principles, namely perceivable, operable, understandable, and robust. The twelve WCAG 2.0 guidelines contain 61 testable criteria.
WCAG 1.0
The first version of the WCAG (named 1.0) was published and became a W3C recommendation on 5 May 1999. These guidelines had a set of 65 checkpoints to test the website. Each of these checkpoints were assigned a priority level based on how important it was to implement.
- Priority 1 (A Level): Web developers must comply with these requirements.
- Priority 2 (AA Level): Web developers should comply with these requirements.
- Priority 3 (AAA Level): Web developers may comply with these requirements.