Facebook

Facebook is a social networking service created by Mark Zuckerberg  and is the most popular social networking site in the world, and the 2nd most popular website in the world, losing only to Google. The name originated from the nickname of directories handed out to university students that aided in getting to know their peers.

History
Facebook was invented by former-Harvard University student Mark Zuckerberg (while at Harvard). Zuckerberg ran it as one of his hobby projects, with financial help from Eduardo Saverin. Originally called thefacebook, Zuckerberg was joined by Dustin Moskovitz and Chris Hughes, and the website soon spread to Yale University and Stanford University, where, like Harvard, it was censored.