WCAG(Web Content Accessibility Guidelines)
WCAG (Web Content Accessibility Guidelines) is the internationally recognized standard defining how to make web content accessible to people with disabilities, organized around four principles — Perceivable, Operable, Understandable, Robust — and three conformance levels (A, AA, AAA). Most legal and organizational accessibility requirements, including the ADA and Section 508, reference WCAG 2.1 or 2.2 Level AA as the practical bar.