This mix of trained and untrained catalogers complicates the reliability of consistent, accurate listings. Lycos introduced brute force indexing of the Internet by using a program often referred to as a spider to search the World Wide Web every day and update its database of indexed sites. Similarly, AltaVista, a search engine developed by Digital Equipment Corporation, also catalogs a vast quantity of pages and has recently added LiveTopics to assist users with refining their search by providing a way to select and eliminate search topics. Such an unstructured approach leads to a lot of hits or nothing at all. A dedicated user can find additional options, generally unique to each search engine's protocol, that claim to refine the search even further.
Some sites even offer the chance to select the importance of one term in a search over another.
While librarians rely on a highly refined cataloging scheme to locate a book in a library, untangling the Web resembles the enigma of the Gordian knot. There simply are no cataloging rules. The vast amorphous tangle that Lycos, AltaVista, Excite, Web Crawler, or any of the other search engines must confront suggests the magnitude of difficulty and frustration awaiting anyone hoping to use the Web as an efficient source of information. A search of the Web for information on Internet agents produces a blizzard of responses that include references to real estate agents, insurance agents, theatrical agents, houses for sale, and so on, often with the most needed pages sorted at the start, then, maddeningly, another burst of relevance appears some twenty to thirty pages of pointless citations later. In short, a simple search is never simple.