Psychoactive drugs are substances that, when taken in or administered into one's system, affect mental processes, e.g. perception, consciousness, cognition or mood and emotions. Psychoactive drugs belong to a broader category of psychoactive substances that include also alcohol and nicotine. “Psychoactive” does not necessarily imply dependence-producing, and in common parlance, the term is often left unstated, as in “drug use”, “substance use” or “substance abuse”.