Horse training.  You either pay someone to do it for you, struggle through it yourself, or unknowingly do it every day.  Most likely, if you have a horse, you are unconsciously training him or her every time you go out to the barn.  Every action you do around your horse sends him a signal which he tries to interpret in order to protect himself or get what he wants.  If you break it down to the simplest of elements, your horse is a very basic creature: he wants to eat, sleep, and basically be left alone.