1. Facebook is a global social networking website. Users can add friends and send them messages, and update their personal profiles to notify friends about themselves. Users can join networks organized by city, workplace, school, and region. Mark Zuckerberg founded Facebook with his friends. He was a student at Harvard University. The website was only for Harvard students at the begining.

2. The website currently has more than 300 million active users worldwide. Facebook had some problems at the begining.It has been blocked in Syria, China, and Iran. Privacy has also been problem. A January 2009 Compete.com study has ranked Facebook as the most used social network by worldwide monthly active users, followed by MySpace.