Guideline 9. Design for device-independence.

Use features that enable activation of page elements via a variety of input devices.

Device-independent access means that the user may interact with the user agent or document with a preferred input (or output) device — mouse, keyboard, voice, head wand, or other. If, for example, a form control can only be activated with a mouse or other pointing device, someone who is using the page without sight, with voice input, or with a keyboard or who is using some other non-pointing input device will not be able to use the form.

Note. Providing text equivalents for image maps or images used as links makes it possible for users to interact with them without a pointing device. Refer also to guideline 1.

Generally, pages that allow keyboard interaction are also accessible through speech input or a command line interface.

Checkpoints:

9.1 Provide client-side image maps instead of server-side image maps except where the regions cannot be defined with an available geometric shape. [Priority 1]

Refer also to checkpoint 1.1, checkpoint 1.2, and checkpoint 1.5.

9.2 Ensure that any element that has its own interface can be operated in a device-independent manner. [Priority 2]

Refer to the definition of device independence. Refer also to guideline 8.

9.3 For scripts, specify logical event handlers rather than device-dependent event handlers. [Priority 2]

9.4 Create a logical tab order through links, form controls, and objects. [Priority 3]

For example, in HTML, specify tab order via the “tabindex” attribute or ensure a logical page design.

9.5 Provide keyboard shortcuts to important links (including those in client-side image maps), form controls, and groups of form controls. [Priority 3]

For example, in HTML, specify shortcuts via the “accesskey” attribute.