WAIS
wide area information servers

A software system used to search indexed databases on remote servers, WAIS returns a ranked list of pages or files that you can retrieve from the server. Another plus to WAIS searching is that it enables you to use so-called natural language input; in other words, you can ask simply "Why is the sky blue?" instead of having to master Boolean AND/OR constructs.

See also: Archie, ftp, Gopher