The first is Smurf Sex. This happens during the honeymoon; you both keep doing it until you're blue in the face.
The second is Kitchen Sex. This is at the beginning of the marriage; you'll have sex anywhere, anytime. Including the kitchen.
The third kind is Bedroom Sex. You've calmed down a bit, perhaps have kids, so you've got to do it in the bedroom.
The fourth kind is Hallway Sex. This is where you pass each other in the hallway and say, "Screw you!"
There is also a fifth kind of sex: Courtroom Sex. This is when you get divorced and your wife screws you in front of everyone in the court.