In an article by The Independent Collegain it is said that Facebook sells the personal information of people who use their service. Most major Web sites have privacy policies. You need to read their privacy policies before you agree to sign up for their service if you don't want your personal information sold to just anyone.
When you write something online you take the chance that your personal information can be found by anyone and used by anyone for anything. If the hosting servies privacy policy says they won't sell your personal information that makes your personal information safer but the things you write can still be stolen.
Facebook says that they will sell your personal information. What that may mean for you is more spam in your inbox among other things.
