The Deep Web

The deep web is by some estimates five-hundred times larger than the free surface web that is indexed by Google and other common search engines. The deep web contains information that may not (for copyright or programming reasons) or cannot be indexed in a text-based web search engine. This includes databases, computer software, multimedia, PDF files and more. For example, BrightPlanet claims that over 350,000 specialty databases exist whose data is not indexed by the standard public web search engines. That is, the search engines cannot or will not look into these databases and index the information that is found there. Other data such as pictures, audio and video files do not contain text content that is searchable, unless someone has specifically created accompanying text data.

 The web sites below provide some access to much of this deep and seemingly invisible set of resources. The databases will have their own private indexes of their information. Some deep web systems require a fee payment for access. If denied access, check to make sure that the fee has not already been paid by some organization. Your nearest library will have specialists interested in providing you with the access or passwords and links that will be needed to reach deeper into this territory, access for which the library has often already paid. To find more current information on this topic, use the search engines to find information on "searchable databases" or the "deep web".
 

  • CompletePlanet (90,000+ databases)
  • Direct Search
  • Invisible-web.net
  • ProFusion (claims access to over 600 GB of data)
  • Search.Com (800+ databases)

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    Parent frame - Pageauthor's Houghton