Recently, Cryptzone, an internet security solutions company, looked at corporate accessibility lawsuits over the past 5 years and determined that every complaint involved at least one of four common accessibility violations.
The most common violation is the failure to provide alternative text for graphic images. Adding alt text is the simplest step that an organization can take to improve its web accessibility and reduce the risk of litigation.
Unidentified or improperly labeled form controls (such as text boxes, check boxes, and radio buttons) render them useless with a screen reader. A third common violation is the use of an inaccessible table. Screen readers must provide the context of where the user is within the table. An accessible table provides this context by identifying at least the column and row “headers.”
Finally, image maps are often inaccessible. Image maps are graphic images that have different “clickable” regions within them—each taking the user to different content. Accessibility can be added by using alt tags in the same way as you would for basic images and adding them to each area.