Accessibility
WCAG
WCAG (Web Content Accessibility Guidelines) is the international standard, published by the W3C, that defines how to make websites usable for people with disabilities, with conformance levels A, AA, and AAA.
WCAG is organized around four principles: content must be perceivable, operable, understandable, and robust. Each principle breaks down into testable success criteria, such as minimum color contrast, keyboard access to every control, and text alternatives for images.
Level AA is the target most organizations and laws point to. WCAG 2.2 is the current version, and it added criteria for focus visibility, target size, and accessible authentication.