Facebook is a great service. I have a profile, and so does nearly everyone I know under the age of 60. However, Facebook hasnt always managed its users data well. In the beginning, it restricted the visibility of a users personal information to just their friends and their “network” college or school. Over the past couple of years, the default privacy settings for a Facebook users personal information have become more and more permissive. Theyve also changed how your personal information is classified several times, sometimes in a manner that has been confusing for their users. This has largely been part of Facebooks effort to correlate, publish, and monetize their social graph: a massive database of entities and links that covers everything from where you live to the movies you like and the people you trust.