Interactivity

• Introduction
• Use add-ons for interactivity only when necessary: Add-on technologies—such as JavaScript and Flash—are not as flexible or as accessible as HTML. Explore standard methods fully before resorting to a nonstandard format.
• Allow users to control the user interface: Users become disoriented when the interface behaves in ways that are inconsistent with expectations. Do not assume control of elements of the interface that belong in the domain of the user, such as window size and cursor position.
• Make interactivity keyboard-accessible: Some users activate elements using the keyboard and will be unable to use an interface that requires point-and-click interaction. Make sure all interactive elements are usable from the keyboard and behave in a manner that is consistent with user expectations.
• Provide an accessible alternate when using a nonstandard format: Some users cannot access interactivity designed using JavaScript or Flash. When providing content in a nonstandard format, provide the equivalent content as accessible HTML.