Habituation is the process of developing a habit. This can involve almost any form of human behavior, from personal traits like parting your hair on one side to a daily routine of particular actions and turning it into a habitual behavior. The actions are said to be 'habituated', and may not even be necessary. The early morning hot drink is a typical habituated behavior. In psychological issues, habituation can become a problem, turning into a compulsive disorder, like obsessive cleaning.