What Are Search Engines?

Back in the old days (the 1980s), the Internet was primarily a research medium. Files were stored separately, with no way to go from one file to another easily. A few systems appeared (Copher and WAIS) to make it easier to find things on the Internet. In 1989 Tim Berners-Lee developed a network of files connected by hypertext links and dubbed it the World Wide Web. The popularity of the Web exploded after the creati of user-friendly browser applications that enabled people to view text and graphics and to jump quickly from page to page. The next thing that was needed was a way for users to find what they wanted, and that's why search engines were created.

A search engine is a database application that retrieves information, based on words or a phrase you enter. How do web-based search engines work? A web search engine employs a program called a search agent (or a spider) that goes out and looks for information on web pages. This information is indexed and stored in a huge database. When you conduct a search, the search engine looks through its database to find entries that match the information you entered. Then the search engine displays a list of the web pages it determines are most relevant to your search criteria.