OCD is when you have specific obsessions and compulsions.

Obsessions are recurring ideas, thoughts, images and impulses that are intrusive and seem senseless.

These include:

Fear of leaving the lights on, the door unlocked or the stove on

Fear of losing things, like your wallet 

Fear of hurting someone by poisoning them

Fear of getting contaminated with germs by touching door handles, sitting in someone's chair, shaking hands

Fear of running someone over in a car

Fear of blurting out obscenities in a church or in public places

Recurring scenes of violence

Compulsions are repetitive behaviours and rituals that are performed to alleviate the anxiety brought on by the obsessions.

These behaviours help neutralize the discomfort you feel when you experience obsessive thoughts.

Compulsions include:

Washing your hands numerous times to dispel a fear of being contaminated 

Checking the stove over and over, or turning it on and off

Counting objects like floor tiles, books in a bookcase

Repeating routines or activities such as looking in a certain direction the right number of times

Collecting and hoarding old newspapers, old movie tickets, wrappers or notes

Spending hours rearranging and straightening paper or things around the house

If you find yourself engaging in behaviours that take up much of your time, may make you late or are embarrassing, you may be suffering from OCD

Compulsive behaviours are different from addictions. 

The difference is that people with addictions get some kind of pleasure out of what they do even if it's temporary.

Whereas people with compulsions always hate the fact they have to perform these ritualistic behaviours.

As bizarre as these actions may sound, they have nothing to do with being crazy