A usable paper document is more than concise text. It also has a consistent graphic design that aids navigation, illustrates concepts, and improves readability. When applying principles of usability to electronic documents that are likely to be viewed on screen, new design issues emerge. These tests led to three primary insights. A poorly designed Web site discourages users immediately.
Sites gain credibility when information is easy to find within an appealing layout.
Most users aren't interested in scrolling for information. Good design, according to the testers of the Sun pages, occurs when all the material, including relevant links, fits on a single screen. Users come to Web pages to browse and search, not to read. If everything is highlighted, then nothing has prominence. Usability Testing Nielsen's team did several types of usability testing.