Yahoo!
Yahoo!
Yahoo! Search is a web search engine, owned by Yahoo! Inc. and was as of December 2009, the 2nd largest search directory on the web by query volume, at 6.42%, after its competitor Google at 85.35% and before Baidu at 3.67%, according to Net Applications.

Yahoo! Search, originally referred to as Yahoo! provided Search interface, would send queries to a searchable index of pages supplemented with its directory of sites. The results were presented to the user under the Yahoo! brand. Originally, none of the actual web crawling and storage/retrieval of data was done by Yahoo! itself. In 2001, the searchable index was powered by Inktomi and later was powered by Google until 2004, when Yahoo! Search became independent.
Reference
Wikipedia
Search Engines
Bing
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DuckDuckGo
Google Search
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Wolfram Alpha
Yahoo!
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