According to a study by the Pew Internet & American Life Project of 1,623 Internet users 18 and older, a full 60 percent don't worry about the amount of information that is available about them online, and only 38 percent have taken measures to limit such information.

The study divided Internet users into four categories based on their level of privacy concerns:

• Unconcerned but careful: 17 percent do not worry about the availability of their online information. Members of this group are active contributors of online content and information but also take some steps to limit their personal information.
• Anxious and proactive: 21 percent of Internet users worry about the availability of their online personal information and actively take steps to limit their own online data.
• Worried but passive: 18 percent are worried about the amount of online information available about them, but do nothing to limit that information.
• Unconcerned and unlimited: 43 percent neither worry about their personal information available online, nor take steps to limit it.