Search tools

Virtual libraries or catalogs

• Value-added collections of Internet resources maintained by one or a small group of individuals. 
• Value is added through the identification, selection, description, evaluation, and organization of resources.
• Resources are often pre-selected and well organized.
• They tend not be comprehensive, but have depth.
• The primary method of navigation is browsing, but searching is generally available.

Internet directories

• Value-added collections of Internet resources maintained by a large group of contributors.
• More comprehensive and less organized than a virtual library.
• Less editorial control.
• Resources are not deep and sometimes of low quality.
• The primary method of navigation is browsing, but searching is generally available
• Unlike search engines, directories are created by humans. Sites must be submitted, and then they are assigned to an appropriate category or categories.
• Because of the human role, directories can often provide better results than search engines. 
• Yahoo is an example of a directory.

Search engines

• Tend to be specialized for specific types of searches.
• Also called "spiders" or "crawlers," search engines constantly visit web 
  sites on the Internet in order to create catalogs of web pages. 
• Because they run automatically and index so many web pages, search engines may often find information not listed in directories.
• To further confuse matters, some search engines also have an associated directory. These are sites that have been reviewed or rated. For the most part, these reviewed sites do not appear as the "default" when a query is made to a hybrid search engine. Instead, a user must consciously choose to see the reviews.
• Meta search engines are not "spiders" or "crawlers", but are engines that search the search engines and directories and then rank results.
  

Proprietary Search Software

This category of search software is a program that is downloaded and installed onto your computer and will access specialized categories that are maintained at a "home" server on the net. These categories are updated along with the underlying search engines. The categories are refreshed on every login and provide rankings by relevance. These types of search software feature specialized categories such as newsgroups, encyclopedias, e-mail addresses, hardware and software evaluations, cars, file searches, games, health news, humor, movies, almanacs, and newspaper articles (although this may require a subscription to the site hosting the news service). 

• Copernic
• Cybot
• SmartRanker (Requires zip decompression software)
• WebRacer