Yahoo! Inc. (NASDAQ: YHOO) is a Worldwide American public corporation with headquarters in Sunnyvale, California, (in Silicon Valley), and provides Internet services worldwide. The company is perhaps best known for its web portal, search engine, Yahoo! Directory, Yahoo! Mail, news, and social media websites and services. Yahoo! was founded by Jerry Yang and David Filo in January 1994 and was incorporated on March 1, 1995.
According to Web traffic analysis companies (including Compete.com, comScore, Alexa Internet, Netcraft, 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.