These guidelines address barriers in Web pages which people with physical,
visual, hearing, and cognitive/neurological disabilities may encounter.
Common accessibility problems on Web sites include: images without
alternative text; lack of alternative text for imagemap hot-spots; misleading
use of structural elements on pages; uncaptioned audio or undescribed
video; lack of alternative information for users who cannot access frames
or scripts; tables that are difficult to decipher when linearized; or
sites with poor colour contrast.