Usability and accessibility

Usability

Usability refers to the ease of use of a website for users. Usability can be achieved by improving ease of control, consistency, flexibility and efficiency of use. Quality documentation also helps make a system more usable as users understand what to do.

Accessibility

Accessibility involves making your website usable by people of all abilities and impairments. Websites should conform to WCAG (Web Content Accessibility Guidelines) and should use semantic HTML, appropriate layouts and alternative text for visual elements. Users may be using assistive technologies such as screen readers, magnification or Braille displays and websites should be compatible with them.

WCAG 2.1

WCAG 2.1 defines 4 accessibility principles.

  • Perceivable - Information and user interface components must be presentable to users in ways they can perceive.

  • Operable - User interface components and navigation must be operable.

  • Understandable - Information and the operation of user interface must be understandable.

  • Robust - Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.