Universal Usability - Principles of Universal Usability Design

Principles of Universal Usability Design

The key to universal usability is recognizing the diversity of user population and user needs. There is no “average” user on whom a system should be based. Although in some cases it is possible to accommodate technology variety and individual differences in one system, multi-layer designs are the most promising approach to achieving universal usability. That is, when a single design cannot accommodate a large fraction of the user population, multiple versions or adjustment controls should be available to users. For example, a novice user can be provided with only a few options; after gaining confidence and experience, the user can choose to progress to higher levels of tasks and the accompanying interface.

Sarah Horton has developed a set of universal usability guidelines for web design. The basic principles are:

• Design simply: Design simple sites, emphasizing important elements and using simple structures and clean, standards-based markup.
• Build well: Take full advantage of these inherent properties, such as fallbacks, flexibility, and user control, to construct universally usable Web sites.
• Favor HTML over other formats: HTML is the best format for universal usability. Provide documents in nonstandard formats, such as PDF and Flash, only as an alternative to accessible html.

Harry Hochheiser and Ben Shneiderman have also developed the Universal Usability Statement Template, which describes a Web site’s content, browser requirements, network requirements, and other characteristics that may influence its usability.