In general, the word addiction refers to some kind of dependence. In the 1970s, the field of psychiatry in North America used the term systematically in the context of dependence on psychoactive substances (drug addiction). However, since then, this term has been used in reference to various types of addictive behaviors, including media addictions. This entry discusses the Internet addiction, which is a specific type of media addiction, and provides some historical perspectives on addictions in general as well as commonalities and causes of addictions.