Facebook is the world's largest social service website, with more than 900 million users. Facebook was launched on February 4, 2004, and officially listed on the NASDAQ stock exchange in the United States on May 18, 2012. Its main founder is Mark Zuckerberg, a graduate student in the Department of Computer Science at Harvard University. Facebook is the world's largest social service website, with more than 900 million users. Facebook was launched on February 4, 2004, and officially listed on the NASDAQ stock exchange in the United States on May 18, 2012. Its main founder is Mark Zuckerberg, a graduate student in the Department of Computer Science at Harvard University.