Glossary

Web Accessibility

Definition: Web accessibility means designing and developing websites so people with disabilities — visual, hearing, motor or cognitive — can use them effectively.

Web accessibility (often abbreviated as a11y) refers to the practice of designing and developing websites and applications that can be used by everyone, including people with disabilities. This encompasses visual, auditory, physical, speech, cognitive and neurological disabilities.

WCAG — The Standard

The Web Content Accessibility Guidelines (WCAG), published by the W3C, are the internationally recognised standard. WCAG 2.1 and 2.2 define success criteria across four principles — POUR:

  • Perceivable — Content is available to all senses (alt text for images, captions for video).
  • Operable — Users can navigate and interact with all controls using keyboard, voice or assistive tech.
  • Understandable — Content and UI are clear and consistent.
  • Robust — Content is compatible with current and future assistive technologies.

Practical Techniques

  • Add descriptive alt text to all meaningful images.
  • Ensure full keyboard navigability (focus styles, logical tab order).
  • Use sufficient colour contrast (WCAG AA requires 4.5:1 for normal text).
  • Use semantic HTML elements (<button>, <nav>, <main>).
  • Provide text transcripts and captions for audio/video content.
  • Use ARIA roles and attributes where semantic HTML is insufficient.
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