Internet privacy

Internet privacy consists of privacy over the media of the Internet: the ability to control what information one reveals about oneself over the Internet, and to control who can access that information. Many people use the term to mean universal Internet privacy: every user of the Internet possessing Internet privacy.

Internet privacy forms a subset of computer privacy. Experts in the field of Internet privacy have a consensus that Internet privacy does not really exist. Privacy advocates believe that it should exist.

Levels of privacy
People with only a casual interest in Internet privacy need not achieve total anonymity. Regular Internet users with an eye to privacy may succeed in achieving a desirable level of privacy through careful disclosure of personal information and by avoiding spyware. The revelation of IP addresses, non-personally-identifiable profiling, and so on might become acceptable trade-offs for the convenience that such users would otherwise lose in using the workarounds needed to suppress such details rigorously. On the other hand, some people desire much stronger privacy. In that case, they may use Internet anonymity to ensure privacy — use of the Internet without giving any third parties the ability to link the Internet activities to personally-identifiable information of the Internet user.

http://en.wikipedia.org/wiki/Internet_privacy