Facebook From Zero to Hero

Facebook is a social networking website that is operated and privately owned by Facebook, Inc.^[1]
Users can join networks organized by city, workplace, school, and
region. People can also add friends and send them messages, and update
their personal profiles to notify friends about themselves. The
website’s name stems from the colloquial name of a book given to
incoming students at Zuckerberg’s high school alma mater, Phillips
Exeter Academy. The book shows the faces and names of the school’s
students and faculty.

Mark Zuckerberg founded Facebook with fellow computer science major students and his roommates Dustin Moskovitz and Chris Hughes while he was a student at Harvard University.^[4] Website membership was initially limited to Harvard students, but was expanded to other colleges in the Boston area, the Ivy League, and Stanford University.
It later expanded further to include any university student, then high
school students, and, finally, to anyone aged 13 and over. The website
currently has more than 250 million active users worldwide.^[5]

Facebook has met with some controversy over the past few years. It
has been blocked intermittently in several countries including Syria,^[6] China^[7] and Iran,^[8] although Iran later unblocked Facebook in 2009.^[9] It has also been banned at many places of work to discourage employees from wasting time using the service.^[10] Privacy has also been an issue, and it has been compromised several times. Facebook is also facing several lawsuits
from a number of Zuckerberg’s former classmates, who claim that
Facebook had stolen their source code and other intellectual property.

A February 2009 Compete.com study has ranked Facebook as the most used social network by worldwide monthly active users, followed by MySpace.^[11]