Search engines, sometimes called search services, allow an individual to search the contents of pages and files on the World Wide Web. Computer scientists develop search engines from software and programs. These programs, often called spiders and robots, search the content of Web sites to develop a database of Web pages.
Learning how to use all the search engines would be a major undertaking. Acquiring knowledge about some of the best search engines is an invaluable skill for effectively searching the Web. Deciding which search engines to use for a particular search and having the skills to formulate effective queries can significantly effect your results. Most search engines have searching capabilities to use Boolean Operators, keyword, phrase searching, field searching, and term proximity searching.
Search engines are categorized similar to print indexes into general, subject, and multithreaded, parallel, megasearch, or metasearch engines.
General search engines contain a broad range of information, develop their own indexes, and search one index. Some are easier to search and provide better results than others. An example of this type of search engine is Google.
Metasearch or Multithreaded search engines search multiple search engines simultaneously. They have the advantages of searching layers of pages rather than an individual search engine. Two major disadvantages of these search services are the lack of control over the search engines execution and they yield limited results. An example of this type of search engine is Ixquick.
Most search engines can be searched in a rudimentary way. Skilled Internet users must take time to learn basic search techniques and characteristics of a few good search engines. It is important to realize that search engines are not perfect and do not yield complete accuracy or comprehensives. Before beginning and completing a search, do the following:
For more information on how search engine strategies see Module 2: Search Strategies.