Yahoo! Inc. (NASDAQ: YHOO) is a United States public corporation with headquarters in Sunnyvale, California, (in Silicon Valley), and provides Internet services world-wide. They include a Web portal, a Web search engine, the Yahoo! Directory, Yahoo! Mail, news, and posting. It was founded by Stanford University graduate students Jerry Yang and David Filo in January 1994 and incorporated on March 1, 1995.
According to Web traffic analysis companies (including Compete.com, comScore, Alexa Internet, and Nielsen Ratings), the domain yahoo.com attracted at least 1.575 billion visitors annually by 2008 according to a Compete.com study. The global network of Yahoo! websites receives 3.4 billion page views per day on average as of October 2007. It is the second most visited website in the U.S., and the most visited website in the world.
On February 1, 2008, Microsoft made an unsolicited bid to purchase Yahoo! for $31 a share, or $44.6 billion for all the shares. Yahoo!'s board of directors rejected the offer on February 11, calling it too low. On May 3, 2008, Microsoft withdrew its offer.