Facebook is a social networking service for high school, college, university, corporate, non-profit, military and geographic communities primarily in English-speaking countries. On September 11, 2006, Facebook announced that it would open its membership up to all Internet users, although no date for the change is currently set. As of December 2005, it had the largest number of registered users among college-focused sites (at over 7.5 million US college student accounts created with an additional 20,000 new accounts being created daily). It is the number one site for photos, ahead of public sites such as Flickr, with 2.3 million photos uploaded daily, and is the seventh most trafficked site in the United States, according to ComScore's MediaMetrix.
Facebook is based in Palo Alto, California. The name of the site is based on the paper facebooks that many colleges give to incoming students, faculty, and staff depicting members of the campus community.