OCD is a disorder which is composed of two parts – obsessions and compulsions.

An obsession is a recurrent and persistent thought or desire. It is not voluntary and can be very distressing.  A person may try to suppress or ignore it but this can be exceptionally difficult.  A compulsion is an uncontrollable urge to perform some repetitive and stereotyped action. This action is not an end in itself but serves as a substitute for unacceptable unconscious ideas and impulses. Although a person may does not know the reason for this action, failure to perform it leads to increasing anxiety, which can be relieved by giving in to the compulsion.

CBT is identified as the recommended treatment for this disorder.