I stated search services come in one of two main flavors. However, the column as it ran failed to discuss the second type of search service available on the Internet. Getting back to the search services I explained that search directories are a collection of web documents, organized by professionals, into a hierarchical, subject-based structure. I also said that search directories are most useful when looking for information in clear categories, such as makers of yogurt or listings of educational institutions. The second type of search services, is the search engine.
Search engines behave differently than directories in that they index words in web documents.
Excite, AltaVista and Infoseek are some of the more popular search engines. To find web site documents in a search engine you ask a question or submit a query. The search engine then matches your query words against the indexed words it has in its databases and presents a listing of possible documents. Typically, search engines are most useful when looking for more difficult topic areas or for those topics that do not fit into the clear categories used by directories. In general, three out of every four search engine users said that they use the Internet primarily for finding information.