Facebook (stylized as facebook) is an American for-profit corporation and online social media and social networking service based in Menlo Park, California, United States.
The Facebook website was launched on February 4, 2004, by Mark Zuckerberg, along with fellow Harvard College students and roommates, Eduardo Saverin, Andrew Mc Collum, Dustin Moskovitz, and Chris Hughes.
Additionally, users may join common-interest user groups organized by workplace, school, hobbies or other topics, and categorize their friends into lists such as "People From Work" or "Close Friends". Additionally, users can complain about or block unpleasant people.
Because of the large volume of data that users submit to the service, Facebook has come under scrutiny for its privacy policies.
Facebook makes most of its revenue from advertisements which appear onscreen. held its initial public offering (IPO) in February 2012, and began selling stock to the public three months later, reaching an original peak market capitalization of $104 billion.
On July 13, 2015, Facebook became the fastest company in the Standard & Poor's 500 Index to reach a market cap of $250 billion.
After registering to use the site, users can create a user profile indicating their name, occupation, schools attended and so on.
Users can add other users as "friends", exchange messages, post status updates and digital photos, share digital videos and links, use various software applications ("apps"), and receive notifications when others update their profiles or make posts.Zuckerberg wrote a program called "Facemash" on October 28, 2003 while attending Harvard University as a sophomore (second year student).According to The Harvard Crimson, the site was comparable to Hot or Not and used "photos compiled from the online facebooks of nine houses, placing two next to each other at a time and asking users to choose the 'hotter' person".To accomplish this, Zuckerberg hacked into protected areas of Harvard's computer network and copied private dormitory ID images.Since 2006, anyone age 13 and older has been allowed to become a registered user of Facebook, though variations exist in the minimum age requirement, depending on applicable local laws.Facebook may be accessed by a large range of desktops, laptops, tablet computers, and smartphones over the Internet and mobile networks.