5 sources

http://www.karenville.com/social-media/social-media-outbreak/

http://socialtimes.com/what-can-psychology-tell-us-about-why-people-go-to-facebook_b27531

http://allfacebook.com/10-ways-facebook-changed-the-world-for-the-better_b53720

http://www.businessinsider.com/10-reasons-to-delete-your-facebook-account-2010-5

http://mashable.com/2008/11/18/social-media-defined/