Metasearch engine
 |
This article relies largely or entirely upon a single source. (November 2010) |
|
|
This article needs additional citations for verification. (November 2010) |
A metasearch engine is a search tool1 that sends user requests to several other search engines and/or databases and aggregates the results into a single list or displays them according to their source. Metasearch engines enable users to enter search criteria once and access several search engines simultaneously. Metasearch engines operate on the premise that the Web is too large for any one search engine to index it all and that more comprehensive search results can be obtained by combining the results from several search engines. This also may save the user from having to use multiple search engines separately.
The term "metasearch" is frequently used to classify a set of commercial search engines, see the list of search engines, but is also used to describe the paradigm of searching multiple data sources in real time. The National Information Standards Organization (NISO) uses the terms Federated Search and Metasearch interchangeably to describe this web search paradigm.
Contents |
Operation
Metasearch engines create what is known as a virtual database. They do not compile a physical database or catalogue of the web. Instead, they take a user's request, pass it to several other heterogeneous databases and then compile the results in a homogeneous manner based on a specific algorithm. The first commercial meta search engine was created by Herman Tumurcuoglu in Montreal, Quebec in 1996. It was dubbed the mother of all search engines Mamma.com
No two metasearch engines are alike.2 Some search only the most popular search engines while others also search lesser-known engines, newsgroups, and other databases. They also differ in how the results are presented and the quantity of engines that are used. Some will list results according to search engine or database. Others return results according to relevance, often concealing which search engine returned which results. This benefits the user by eliminating duplicate hits and grouping the most relevant ones at the top of the list.
Search engines frequently have different ways they expect requests submitted. For example, some search engines allow the usage of the word "AND" while others require "+" and others require only a space to combine words. The better metasearch engines try to synthesize requests appropriately when submitting themcitation needed.
See also
- For engines, see the list of search engines
References
- ^ Sandy Berger's Great Age Guide to the Internet By Sandy Berger. Que Publishing, 2005, ISBN 0-7897-3442-7.
- ^ Manoj, M Elizabeth, Jacob (October 2008). "Information retrieval on Internet using meta-search engines: A review". CSIR. pp. 739–746. Retrieved February 25, 2012.
External links
- Metasearch at the Open Directory Project
- Guide to Meta-Search Engines by UC Berkeley libraries with recommendation not to use them for serious research.
- Meta-search: More heads better than one? Argument against Berkeley's negative recommendation
|
|||||||||||||||||
Content from Wikipedia, the Free Encyclopedia
What Is This Site? The Ultimate Study Guide is a mirror of English Wikipedia. It exists in order to provide Wikipedia content to those who are unable to access the main Wikipedia site due to draconian government, employer, or school restrictions. The site displays all the text content from Wikipedia. Our sponsors generously cover part of the cost of hosting this site, and their ads are shown as part of this agreement. We regret that we are unable to display certain controversial images on some pages the site at the request of the sponsors. If you need to see images which we are unable to show, we encourage you to view Wikipedia directly if possible, and apologize for this inconvenience.
A product of XPR Content Systems. 47 Union St #9K, Grand Falls-Windsor NL A2A 2C9 CANADA