The Web Accessibility Initiative’s ARIA specification is a useful way of adding additional information to Ajax applications to allow them to pass information to assistive technologies to make them accessible.
I agree with criticism that it’s a bit of a hack, and it doesn’t stop sloppy authors using the wrong element for the job, but I think that’s unavoidable—emultaing desktop applications in a browser using creaky ol’HTML 4 is itself a bit of a hack. It’s also the only show in town when it comes to accessible “web 2.0” until HTML 5 comes along in a decade, especially now that all the major browsers and screenreaders have some degree of support. There’s now extra ARIA goodness in Gmail and WordPress 2.6.
But what actually is it, I found myself asking while researching it, and so commissioned Gez Lemon to write an article for the Opera Developers community.
Ladies and gentlemen: An Introduction to ARIA by Gez Lemon (comments there, please).