WCAG POUR Principles
The four principles behind web accessibility: Perceivable, Operable, Understandable and Robust.
Why it matters
Products must work for people with different abilities, and this is often a legal requirement too.
The essentials
- Perceivable: people can sense the content, with text alternatives and enough contrast.
- Operable: everything works by keyboard and gives enough time.
- Understandable: content is clear, and behavior is predictable.
- Robust: it works with assistive technologies.
How to use it
- Check contrast.
- Test using only a keyboard.
- Use real labels and headings.
Example
A form error that is shown only in red fails people who cannot see the color, so add text too.