there half chaps. ridders use them so they don't get rubs on there legs.
only some....
To protect the rider's legs
Horse riders wear spurs to make the horse go faster (Foot Item)
In UK a motorcyclist must wear a helmet - not sure about cyclists or horse riders
There are hundreds of thousands of French horse riders.
The skilled horse riders who were nomads were mosveans.
Horse riders in competition are "equestrians", just atop a horse is the adjective "mounted".
The sole purpose of spurs is to act as a leg aid. For riders that have weak legs or horses that tend to be 'dead sided', spurs are a great way to communicate to your horse. Spurs in the wrong hands, however, can do great damage to the horse. Sharp edged spurs should never be used. Small, smooth spurs are all that is needed as an extension of the riders legs and heels.
Polo wraps are usually placed on a horse's legs for protection and/or support during exercise. Depending on the horse and his job, he may wear wraps on all four legs, just two, or not at all.
It depends on the state and/or country you live in. Most places that require riding safety helmets for junior riders, the cutoff age is 18 years. If you are at a horse show all riders may be required to wear helmets due to the liability insurance reguardess of age.
If you meant 'why do riders wear boots?', then I'm fairly certain you can answer that yourself. It is the same reason you were shoes: we wear shoes to protect our feet. If you meant 'why do the horses wear boots?', then the answer is, again, to protect their legs.
Trotting is a gait, but skipping isn't. Trotting is like running, and the horse's legs move in diagonal pairs. In English riding, riders post to the trot. Winnie the Horse Gentler