WIA-ARIA for short is targeted to assist users with disabilities to enjoy the web to the full extent. This initiative provides defined ways and means for users with disabilities [using screen readers, inability to use mouse, only keyboard etc] who use assistive technologies to access the web meaningfully.
The identified problems with assistive technologies are that sometimes disabled users are unable to interact with the web page items especially those that are related to dynamic web content such as AJAX, Javascript, DHTML and related technologies.
WAI-ARIA provides the information necessary for the assistive technologies to effectively interact with these new web features.
If you are a web developer and interested in using this very important development you should visit the following link.
http://www.w3.org/TR/wai-aria-practices/