There are so many search engines available on Internet.
Most of the users want only a single search engine that delivers basic key features as

• Relevant results (results you are actually interested in)
• Uncluttered, easy to read interface
• Helpful options to broaden or tighten a search
• Quick response (less time consuming)

I prefer Google.Google is fast, relevant, and the largest single catalog of Web pages available today
Below are some other Search engines available, these are also used very much by the people.

http://www.bing.com/
Alexa Rank : 27
Estimated Unique Monthly Visitors : 165,000,000

http://www.yahoo.com/
Alexa Rank : 4
Estimated Unique Monthly Visitors : 160,000,000

http://www.ask.com/
Alexa Rank : 52
Estimated Unique Monthly Visitors : 125,000,000

http://search.aol.com/
Alexa Rank : 64
Estimated Unique Monthly Visitors : 33,000,000

http://mywebsearch.com/
Alexa Rank : 118
Estimated Unique Monthly Visitors : 19,000,000

http://www.lycos.com/
Alexa Rank : 1640
Estimated Unique Monthly Visitors : 4,300,000

http://www.dogpile.com/
Alexa Rank : 3617
Estimated Unique Monthly Visitors : 2,900,000

WebCrawler
http://www.webcrawler.com/
Alexa Rank : 6358
Estimated Unique Monthly Visitors : 2,700,000

http://www.info.com/
Alexa Rank : 3038
Estimated Unique Monthly Visitors : 2,600,000

http://www.infospace.com/
Alexa Rank : 1862
Estimated Unique Monthly Visitors : 2,000,000

http://www.search.com/
Alexa Rank : 5903
Estimated Unique Monthly Visitors : 1,450,000

http://www.excite.com/
Alexa Rank : 4422
Estimated Unique Monthly Visitors : 1,150,000

http://www.altavista.com/
Alexa Rank : 7676
Estimated Unique Monthly Visitors : 700,000

Note : All the above data related to search engines have collected on dated 03/31/2012.