This social media network was launched on 4 February 2004 by Mark Zuckerberg and his college roommates Eduardo Saverin, and Chris Dustin Moskovitz Hudges. Nowadays each user spends an average of 40 minutes per day on social networking; it's impossible to block Mark Zuckerberg and the picture that has received the most 'likes' is the picture of Barack Obama embracing his wife, Michelle Obama.