Originally Posted by eric_B
Small derail: who or what is an OCD?
Obsessive Compulsive Disorder, very basically an anxiety caused by things not being a certain way, and behaviors that become habits are used to cope with that anxiety. Such habits might include constant washing of hands, knocking on a door a certain # of times (like Sheldon on Big Bang Theory) etc. Someone who is very meticulous and checks things 3 or 4 times when not really necessary, would be considered OCD. Those who are particularly obsessed sort of jokingly call it CDO, as the letters are then in alphabetical order.