What does WAI-ARIA offer to improve the accessibility of widgets?
ARIA provides authors with the following: • roles to describe the type of widget presented, such as “menu”, “treeitem”, “slider” or “progressmeter” — elements which do not exist in current HTML 4.01. • roles to describe the structure of a web page • properties to describe the state widgets are in. Examples include valuenow=”50%”, required=”true”, expanded=”true” etc. • properties to define live regions of a page that are likely to get updates (such as stock quotes), as well as an interruption policy for those updates. • properties describing drag sources and drop targets • a way to provide keyboard navigation for JavaScript widgets in HTML.