The result of a user agent rendering the contents of a delivery unit. User agents may or may not render all information in a delivery unit. In some cases, a single delivery unit may be rendered as multiple perceivable units. For example, a single html file that is rendered as a set of presentation slides. Most perceivable units contain presentation and the means for interaction. However, for some devices such as printers, a perceivable unit may only contain presentation.
Task:
Allow users to skip over blocks of repeated material
Web pages often include content that appears on other pages within the same site. Examples include, but are not limited to:
Navigation links,
Header graphics,
Advertising frames,
Etc.
Web content is often organized in ways that make it difficult for people with some disabilities to reach the main content quicly and easily. Screen reader users who visit several pages on the same site may have to hear all header graphics and dozens of navigation links on every page before the main content is spoken. People who use only the keyboard or a keyboard interface might have to make dozens of keystrokes before reaching a link in the main content area. This can take a long time and may cause severe physical pain for some users.
Most users are able to ignore such repeated material. They can look at the center of the screen, where main content usually appears. They can select a link or button with a single click of the mouse without encountering each link or form control that comes before the item they want.
Designers can use simple techniques to help users with disabilities skip over repeated material and reach main content quickly and easily. These techniques include, but are not limited to:
Adding a link at the top of each page that goes directly to the main content area
Using markup to identify navigation and content areas
Providing keyboard access to important links and form controls
Designing information so that content comes before repeated material; this may require giving users a way to reach the navigation area quickly