Making pages usable by everyone, following the Web Content Accessibility Guidelines.
The Web Content Accessibility Guidelines (WCAG) are the international standard for accessible web content, organized around four principles known as POUR: Perceivable, Operable, Understandable and Robust. They define conformance levels A, AA and AAA, with AA being the common legal and practical target. In HTML terms this means text alternatives for images, sufficient color contrast, labelled form controls, captions for video, keyboard operability, visible focus indicators and a logical heading and landmark structure.
The best accessibility strategy is to start with semantic HTML, because native elements like button, a and input come with keyboard support and the right roles built in. ARIA attributes such as aria-label, aria-expanded and role should supplement semantics only when native elements can't do the job; the first rule of ARIA is not to use ARIA if a native element exists, since incorrect ARIA is worse than none. Interviewers also expect awareness of testing with screen readers, keyboard-only navigation and tools like axe or Lighthouse.
What you'll walk away knowing