Facebook (stylized as facebook) is a 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.

The founders had initially limited the website's membership to Harvard students; however, later they expanded it to higher education institutions in the Boston area, the Ivy League schools, and Stanford University.

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 can be accessed by a large range of desktops, laptops, tablet computers ,and smartphones over the Internet and mobile networks.

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.

Facemash attracted 450 visitors and 22,000 photo-views in its first four hours online.

The site was quickly forwarded to several campus group list-servers, but was shut down a few days later by the Harvard administration.

Zuckerberg faced expulsion and was charged by the administration with breach of security, violating copyrights, and violating individual privacy. Zuckerberg expanded on this initial project that semester by creating a social study tool ahead of an art history final exam.

He uploaded 500 Augustan images to a website, each of which was featured with a corresponding comments section.

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.