Metasearch engine
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A metasearch engine is a search engine that sends user requests to several other search engines and returns the results from each one. They allow users to enter their search criteria only one time and access several search engines simultaneously. Since is hard to catalog the entire web, the idea is that by searching multiple search engines you are able to search more of the web in less time and do it with only one click. The ease of use and high probability of finding the desired page(s) make metasearch engines popular with those who are willing to weed through the lists of irrelevant 'matches'.
Metasearch engines do not compile databases or catalog the web. They act as a middle-man, taking a user's request and passing it to several other search engines.
No two metasearch engines are alike. Some only search 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. Some will list results according to search engine. This allows the user to see which search engines are returning hits along the lines of what they are looking for. If the user wants to pursue deeper, they can then go to that particular search engine's page and repeat the search there. Others return results according to relevance, often concealing which search engine returned which results. This benefits the user by eliminating duplicate hits and clumping the most relevant ones at the top of the list. One metasearch engine, Dogpile, allows you to choose how results are presented.
Search engines frequently have different ways they expect requests submitted. For example, some search engines let you use the word "AND" while others require "+" and others only require a space to combine words. The better metasearch engines try to synthesize requests appropriately when submitting them.
Results can vary between metasearch engines based on a large number of variables. Still, even the most basic metasearch engine will allow more of the web to be searched at once than any one stand-alone search engine.
See also
External links
- Guide to Meta-Search Engines (http://www.lib.berkeley.edu/TeachingLib/Guides/Internet/MetaSearch.html)
- Paper refuting Berkeley Guide's disrecommendation of meta-search (http://news.zdnet.com/2100-9588_22-5647280.html)
Meta-search engines
- Apollo7 (http://www.apollo7.co.uk) searches over the major searchenigines
- Clusty (http://www.clusty.com) – returns clustered results
- Dogpile (http://www.dogpile.com)
- Kartoo (http://www.kartoo.com) – a map-based meta-search
- Mamma (http://www.mamma.com) – one of the first metasearch engines
- Metacrawler (http://www.metacrawler.com) – searches major search engines
- metaEUREKA (http://www.metaeureka.com)
- Yooci (http://www.yooci.com) – international metasearch engine
- search.com (http://www.search.com) by CNET
- Don Busca (http://www.donbusca.com)
- everyclassified.com (http://www.everyclassified.com) – search engine that re-directs user queries to the most relevant classifieds web-sites.