Web Content Accessibility Guidelines a guide to the accessibility requirements
4 Robust

4.1.2 Name, Role, Value

Conformance level: A
Criterion released in WCAG version: 2.0

Official description of the success criterion

For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies. 

What to do?

Ensure that user interface components have clear names, roles, and states.

Why is it important?

Supports assistive technologies in communicating content and functionality accurately.

Common pitfalls

Using HTML elements incorrectly and not providing an ARIA role for them.

How to test for it?

Automated tools can catch some of the problems with this criterion.

More about this criterion elsewhere