Within each broad category there are one or more layers of sub-categories leading to Web page entries. Entries include some descriptive text. Alta Vista premiered in December of 1995. The search service is produced and supported by Digital Equipment, primarily as a demonstration project for Digital hardware and software development. Alta Vista currently indexes over 30 million Web pages.
Result sets can be large without semblance of relevance ranking, thus time-consuming to sift.
The advanced search also allows for some user control over the ranking of the result set. They index about one and a half million sites and provide reviews on a little over 40,000. The list of sites is searchable by keyword string, but with no boolean operators. Results are presented in the form of an annotated list with links to the site entries and to a review, for those sites that have been reviewed. Reviews include a short narrative about the site, keywords for classifying it, intended audience for the material, and link and access information.