reining is basically dressage but for western. You have a pattern your required to do different stride changes. Now dressage has more things asked but you get my idea.
Reining has a total of between 6-10 patterns. (can't remember exactly) But you are asked to do a pattern. Every reining pattern deals with circles, either 2 fast circles and one small circle for the left side, or visa versa. Then you have to do a figure 8, roll back (in a stop the horse turns on a dime), sliding stops (my favorate), flying lead changes, and backing up. NRHA.com has patterns for you.
I used to show in reining, my trainer is known for reining. Him and I went to a show and I screwed up the pattern, it wasen't that bad (I forgot a lead change) anyway when I came out of the ring, he yelled at me, ripping me up one side and down the other. I tried to do reining again at another show but I messed up again, same thing got yelled out. Needless to say I don't ride for this trainer anymore. I'll probley never be able to show in reining. When ever I try to pratice a pattern I swear I see him in the ring. Either I pull the horse up to a stop or I fall off. But overall I love the event. I loved doing a sliding stop.
showed in reining for a while