If any one search engine covers only a fraction of the web, how can you perform a comprehensive search? One solution is the metasearch engine. This type of search engine submits your search to several search engines and then compiles the various results sets into one results list.
Pro’s
Useful when you want to do a comprehensive search of a number of sources.
Eliminating duplicate results saves time.
Con’s
It can produce an unmanageable number of search results.
Some advanced searching features may not be available.
List of Metasearch Engines