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Search Engines and Subject Directories

The Internet and World Wide Web make it much more convenient to quickly locate information; however, the vast amount of information on the Internet and the fact that anyone can publish on the Web makes it imperative that users know how to locate high quality, reliable information.

Using Search Engines to locate information on the Internet

  • Many search engines are available
  • Different search engines produce different results
  • Search engines locate Web sites via web robots or by individuals who submit a URL for a resource
  • Search engines usually include sites without regard to content or quality
  • Search engines include millions of Web sites; retrieve thousands per search
  • Users must know how to search efficiently and effectively
  • Users must also know how to determine quality of Web sites (see Evaluating Resources)
  • No search engine indexes all Internet resources

Using Subject Directories to locate information on the Internet

  • Sites may be identified by humans or computer robots, but are selected because they contain certain terms or are from certain domains (.edu, .gov)
  • Sites are selected based on quality and/or content
  • Web sites are arranged by subject category
  • Some subject directories are huge; may appear to be a search engine (e.g., Yahoo!);
  • When you use a subject directory you are only searching the resources in that directory.
  • Search will not retrieve as many Web sites as a Search Engine
  • First level of filtering is already done for you
  • No subject directory includes all resources on a topic

Which to use? Search Engines? Subject Directories?

  • Remember: No search engine or subject directory includes all Internet resources
  • You may want to use a combination depending on the type of information you are looking for and how exhaustive you want your search results to be.
  • Subject directory = a subset of resources on the Internet (the first level of filtering has already been done for you.
  • Search engine = more resources but no check for content or quality

Search Engine Showdown
This site compares search features of the major search engines and subject directories, cites statistics such as size, retrieval time, and percent of dead links, lists new search engines, and much more. How does your favorite search engine measure up?

Page last updated: August 27, 2007
Questions or suggestions? Contact Gerri Wanserski