Using images in web sites automatically introduces accessibility issues for some people, who are unable to see them, but at the same it could be an accessibility facilitator for others. Read more about how to use images in web sites at their best potential, and how to make sure that they are accessible for all.
The Accessible Rich Internet Applications (WAI-ARIA) specification defines roles, states, and properties that should be used to provide semantics in languages where they may not be available. Assistive technologies, such as screen readers, use what ARIA offers in order to communicate with browsers to present information about the status of interactions, and the like. As a result, WAI-ARIA is especially important to consider when creating dynamic content.