Bing was launched on June 1, 2009. Prior to that, it was known as MSN Search, Windows Live Search and simply Live Search at different points. Less than two months into its launch, Microsoft and Yahoo! announced a ten-year deal in which Yahoo! Search results would be provided by Bing, with Yahoo! keeping 88% of revenue earned in the first five years.
As of November 2015, analytics company comScore reported that Bing was the second most-used search engine, accounting for 20.9% of web searches. The Bing-powered Yahoo! Search scored at 12.5%, giving Bing a overall share of 33.4% - just over a third of all web searches.