ARIA (accessible rich internet applications), is a way of programmatically adding roles, states and values to a web control that is not part of the HTML standard controls. It is used by assistive technology to provide feedback about a non-standard control. It can also be used to give additional information such as a page section that may only be visually indicated like the banner, navigation or main page section.
These five articles look at different uses of ARIA and help explain there purpose in accessibility.
1. WAI-ARIA Overview
This is the W3C WAI official site on ARIA, where the standards are documented. It may not be the easiest thing to read but it is the most accurate.
2. How to use ARIA: An introduction
This is the first part of a series on learning to use ARIA in your rich internet applications. It covers what ARIA can be used for and why.
3. ARIA Slider, Part 1
This article explains how to use ARIA to help create an accessible slider web control. It is divided into three parts. Note, the need for attention to how the script interacts with the user has a large baring on the level of accessibility.
4. Accessible drag and drop with multiple items
This article goes over how to code an accessible drag and drop feature of a web application using ARIA to help with accessibility. Note, ARIA is only part of the solution and care is required in the way the script handles user interaction, for example it needs both keyboard and mouse controls.
5. WAI-ARIA FAQ
This is the W3C frequently asked questions on ARIA and addresses many of the common questions developers and content authors have about ARIA and its uses.