HyperHistory Online is a collection of hypertextual timelines that graphically display 3,000 years of world history. The timelines use charts, images, maps, and color-coded text to provide "synchronoptic" views of history. These spatial representations of time allow users to regard and compare the various associations among related and unrelated people and events throughout history. This extensive site consists of three major timeline indexes that cover important persons, significant events, and general world history. Each index includes several specific timelines arranged according to chronological period. Names of people, places, and events on the timelines link to brief historical narratives. In addition, a large collection of interlinked maps provides geographic contexts for the histories. HyperHistory Online also includes an alphabetical index of 800 people and provides 328 links to related Websites.