Invisible, Deep, or Hidden Web

What is the Invisible Web?

The invisible web is the portion of the web that is not searched by general search engines. It is sometimes referred to as the hidden or deepweb. As the amount of information published on the web has grown, web site developers have turned to databases as a means of managing the increasing amounts of data. These databases are searchable with site-specific search engines, but are not searched by general search engines (individual or meta-searchers).

Although the invisible web has gained attention recently, it is not a new phenomenon. You have already searched portions of the invisible web when you've accessed library catalogs or information services, such as OCLC FirstSearch, Digital Pipeline, CSA, etc.; read the New York Times online; used an online calculator; or accessed information that is stored in a database. These are sites or pages that are restricted to login, are fee-based or subscription, are protected by firewalls, are generated in response to a query, or cannot be searched because of format.

Some examples of Alaska-based invisible web resources are:

  • Fairbanks North Star Borough maps & GIS, and the property database. The information in these databases contain public record information that historically would be available to people by visiting the county clerks office. The information is now online, but is not indexed or crawled by common search engines.
  • Alaska Trial Court Cases. The information in this database contains public records that historically would be found in the Alaska Court Clerks office. This information is available online, but is not indexed or crawled by common search engines.

Searching the Invisible Web

Companies have been developing search engines to search the invisible web and are now making these tools available. Rather than retrieving web pages or documents, invisible web search engines direct the user to an appropriate searchable database. Some even generate a search form for your convenience.

Searching the invisible web is actually a two-step process.

First, locate the appropriate database to search. Browsing is the easiest method. Invisible web search engines are accompanied by a categorized list or subject directory. Browse the appropriate category to make your selection. Or, you can use keywords, including natural language, to search for a database using the search engine. Searches should be kept simple.

Second, search the database you just located. Review the HELP screens for tips on improving the effectiveness of your search query.

Selective List of Invisible Web Search Tools

This page was last modified on April 13, 2015