Among the best-known names on the Internet, Yahoo was one of the first companies that enabled users to find their way online, but it has lost its role as a leader.
Here are key facts about Yahoo:
Founded in 1994 by Stanford University students David Filo and Jerry Yang, Yahoo was created as a type of directory for the Internet. It was originally called "Jerry and Dave's Guide to the World Wide Web" and when the Yahoo name was agreed upon, its founders said in jest that it stood for "Yet Another Hierarchical Officious Oracle."
Its initial public offering in 1996 was the largest for a tech startup at the time.
Based in Sunnyvale, California, Yahoo has offices around the world and employs 11,000 people. Marissa Mayer was named chief executive in July 2012.
Yahoo was once the leading search engine for the Internet but it has been overtaken by Google, which launched in 1998.
According to the research firm comScore, Yahoo handled 12.7 percent of online searches in August compared with 64 percent for Google and 20.4 percent for Microsoft's Bing.
For online advertising, Yahoo is only expected to take 2.3 percent of global online search revenues for 2015, trailing Google, Microsoft and China's Baidu, according to eMarketer.
With its Web portal, Yahoo remains an important online destination for email, messaging, news, and video. It gets 210 million regular visitors for its news and email alone in the United States, according to comScore.
In October, Yahoo became the first online service to stream a regular season NFL football match, getting 15 million viewers.
Yahoo's finances have been skewed by its stake in China's Alibaba.
It bought a 40 percent stake in Alibaba in 2005 for $1 billion and its current holding of some 15 percent is now worth around $30 billion -- the vast majority of Yahoo's market value of around $33 billion.
In 2013, Yahoo moved to attract a younger audience by buying the online blogging platform Tumblr for $1 billion.
Yahoo posted a net profit for 2014 of $7.5 billion but much of that came from the sale of Alibaba shares. Its revenues for the year were $4.6 billion.
