Facebook is a social network for connecting people with those around them – friends, family, coworkers, or simply others with similar interests. Facebook started in 2004 as a closed community for college students (requiring users to sign up with a valid university email address) but has since expanded beyond that to schools, corporations, and any user across the world. Facebook allows users to connect and share information in a variety of ways.

Facebook currently has over 750 million active users, and that number continues to grow steadily. According to Compete.com, it is currently the second most popular website in the world (behind Google) in terms of unique visitors, and according to ComScore, the most popular social network overall.
Think your customers aren't on Facebook? There are tens of thousands of work-related, collegiate, and high school networks. According to InsideFacebook.com, approximately two thirds of U.S. Facebook users are outside of the college demographic, and users age 26 to 64 make up more than half of Facebook's U.s. user base. While Facebook started off as a community for college students, it has expanded far beyond that, and you'd be hard-pressed to find a demographic not yet represented among Facebook's 750 million users.