Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. A persistent dependence on a behavior is known as addiction. The term, initially employed to describe physical and psychological enslavement to psychoactive substances, has been altered and extended – today the word “addiction” includes mood-altering behaviors and activities as well. Moreover, today non-substance-related addiction is considered as a health problem as grave as substance dependence. Learn more about behavioral addiction and its main types in this book.