Privacy is the ability of an individual or group to seclude themselves or information about themselves, and thereby express themselves selectively. The boundaries and content of what is considered private differ among cultures and individuals.
When something is private to a person, it usually means that something is inherently special or sensitive to them. The domain of privacy partially overlaps with security, which can include the concepts of appropriate use, as well as protection of information. Privacy may also take the form of bodily integrity. The right not to be subjected to unsanctioned invasions of privacy by the government, corporations or individuals is part of many countries' privacy laws, and in some cases, constitutions.
Internet privacy involves the right or mandate of personal privacy concerning the storing, repurposing, provision to third parties, and displaying of information pertaining to oneself via the Internet. Internet privacy is a subset of data privacy. Privacy concerns have been articulated from the beginnings of large-scale computer sharing.
Sources: Privacy (Wikipedia) and Internet Privacy (Wikipedia)