It is a form of psychological treatment. In behavioral therapy, the goal is to reinforce desirable behaviors and eliminate unwanted or maladaptive ones. The techniques used in this type of treatment are based on the theories of classical conditioning and operant conditioning.
Classical conditioning involves learning by association and is usually the cause of most phobias. Operant conditioning involves learning by reinforcement (e.g. rewards) and punishment, and can explain abnormal behavior should as eating disorders.