Each new technology, always, is related to opportunities and threats. To take advantage of opportunities but eliminate or at least reduce threats, legal solutions are applied, which forbid some practices that are technically possible but socially inacceptable. A technology that has provided people with endless opportunities and deeply changed human lives is information technology (IT). It, however, is not free of threats, which are particularly hard to deal with. Among them, one of the most significant is breach of privacy. The concept of privacy is broad. It may concern individuals, organizations, businesses, public institutions, and states. It is also multifaceted. Among the facets are, for example, the following:

Statutory aspects of privacy—e.g., the United Nations Universal Declaration of Human Rights, the Data Protection Directive of the European Commission, the US Health Insurance Portability and Accountability Act, and the US Family Educational Rights and Privacy Act

Technical aspects of privacy—e.g., information gathering, information flow control, and information leakage

Societal aspects of privacy—e.g., what information is private and how it is handled

Political aspects of privacy—e.g., the surveillance state and population control