Bing (formerly Live Search, Windows Live Search, and MSN Search) is a web search engine (advertised as a "decision engine"[1]), Microsoft's current incarnation of its search technology. Unveiled by Microsoft CEO Steve Ballmer on May 28, 2009 at the All Things Digital conference in San Diego, Bing is a replacement for Live Search. It went fully online on June 3, 2009,[2] with a preview version released on June 1, 2009. In its first few weeks Bing was successful in gaining some market share.[3]

Notable changes include the listing of search suggestions in real time as queries are entered, and a list of related searches (called "Explorer pane" on the left side of search results), based on semantic technology from PowerSet[4] which Microsoft purchased in 2008.[5] Bing also includes the ability to Save & Share search histories via Windows Live SkyDrive, Facebook, and email.

Most of the new features in Bing currently are only available in the United States
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