The person with OCD suffers from obsessions and compulsions. Obsessions are recurrent and persistent thoughts, impulses, or images that are disturbing, intrusive, and inappropriate, and which result in marked anxiety or distress. These thoughts and worries are not simply excessive worries about real life events or problems. You might attempt to ignore or suppress the thoughts, impulses, or images, or neutralize them with another thought or action, but recognize that these events are coming from your own mind.
Compulsions are repetitive behaviors (such as germ avoidance, hand washing, ordering, checking, hoarding) or mental acts (counting, repeating words silently, praying compulsively) that you feel driven to perform in response to an obsession, or certain rules that have been adopted and must be applied. These behaviors and mental acts are designed to prevent or reduce distress or some dreaded event or situation, even though in reality there is no connection.