Fwiw, there are two disorders, OCD and OCPD, with very similar labels, and although "OCD" has become shorthand, it's actually OCPD (Obsessive Compulsive Personality Disorder) that most people are referencing. I'll give you the short version:
OCD - obsessions and compulsions (see above). Examples: washing your hands 20 times even though they are clean, checking your door or window locks for hours, even though you "know" they are locked; counting to yourself over and over; cleaning obsessively out of fear of contamination; hoarding (like on the TV show).
OCPD - perfectionism, excessively detail oriented, excessive need for order and organization, "anal" personality, overly structured and rule-oriented, driven to always be "productive," hard time relaxing and going with the flow, etc.
When people say "I'm OCD," they usually mean the latter, not the former. It's confusing, because we've got two different disorders with "obsessive compulsive" in the title.