There are basically two types of information collected online: aggregated information and personally identifiable information. Aggregate information is statistical, whereas personally identifiable information includes things like name, address and phone number.
When you visit a website, your Web browser automatically turns over quite a bit of aggregate information as a matter of course. The specific Web browser you are using and your operating system are two examples of non-identifying, statistical information. Your browser also necessarily hands over your Internet Protocol (IP) address; the unique number that identifies your specific computer on the Web. Without sharing this unique identifier, you would not be able to participate on the Internet.
Sites that engage in commerce, requiring personal information and credit card numbers, should also state on the privacy page how this information is protected. Secure access should be allowed by the owner of that information to update the information as necessary.
Controversy over privacy policies of popular socializing sites sometimes make headline news. Participants of sites like YouTube™, Facebook™, MySpace™ and LinkedIn™ provide a plethora of personal information, including digital photographs, personal videos, blogs, podcasts and more. The more personal information one intends to share, the more vital it is to review policies before participating. Aside from privacy concerns, one might want to be sure that he or she maintains copyright to original works posted, rather than the copyright automatically becoming property of the website.