When did the website "Facebook" launch?

The story behind the answer

Facebook launched on February 4, 2004—originally as “TheFacebook”—created by Mark Zuckerberg with fellow Harvard students Eduardo Saverin, Andrew McCollum, Dustin Moskovitz, and Chris Hughes. It first served Harvard, then spread to other universities before going mainstream. This date distinguishes it from later milestones: the name change to “Facebook” in 2005 and the public opening to anyone 13+ in 2006, which can make 2005 or 2006 seem plausible but are not the launch.

To remember: think “2/04” (February 4) pointing to the year 2004. Also recall the sequence: campus (2004), rebrand (2005), open to all (2006). This timeline marks Facebook’s rapid evolution from a college directory to a global social network.