There are two basic styles of riding in the United States: English, in which a saddle with a relatively flat seat is used, and Western, in which a deep-seated saddle is used.

Bridles, saddles, and other equipment used for riding are, collectively, called tack.

A bridle consists of a headpiece (the headstall), a bit, and reins. The bit, held in the horse's mouth, is used to control the animal's movements. It, in turn, is controlled by the reins, held by the rider.

There are two main kinds of bits. The snaffle bit is a straight bit without shanks and is often jointed in the middle. A pull on the reins exerts direct pressure on the horse's mouth. The snaffle is a very mild bit. It is used for training horses and for jumpers, race horses, and other light horses where not much restraint or fine cueing is needed. The curb bit has a shank on each side, to the ends of which the reins are attached. A slight pull on the reins exerts pressure on the horse's chin, via a chin strap or chain, and on the inside of the horse's mouth.

A full bridle, used in formal English-style riding, has both a snaffle and a curb bit with a headstall for each. A single bridle is a bridle with only one bit. A double-rein bridle is a full or single bridle with two sets of reins; the rider holds four reins—two from each side. The single-rein bridle has only one set of reins. A Pelham bridle is a single bridle with a Pelham curb bit. It has a second set of reins attached to the upper shank of the bit; these function as snaffle reins. The Pelham bridle is common in English pleasure riding. A single-rein bridle with a curb bit is standard in Western riding in most parts of the United States.

A halter has no bit and is used to lead and to tie horses. A hackamore, in its simplest form, is similar to a bridle but instead of a bit uses a noseband to squeeze the nose and jaw when the reins are pulled. Hackamores are widely used in training young horses; they are also used on horses with injured mouths and should be used by heavy-handed riders.

The English-style saddle is a light saddle with a relatively flat seat. It is used for jumping, Thoroughbred racing, polo, and English-style show and pleasure riding. The lightest version, used for racing, weighs up to 2 pounds (900 g).

The Western saddle usually weighs about 40 pounds (18 kg). It has a comparatively high back and front with a horn atop the front. This saddle was developed as a secure, comfortable, all-day saddle for the working cowboy. A saddle blanket underneath the saddle protects the horse's back against getting sore.

In both English and Western riding the aim is harmony of horse and rider. Riders learn to balance themselves in accord with their horses' movements. They also learn to control the direction, speed, and type of movement by subtle use of pressure on the bit through the reins, pressure of their legs, position of their body, and sometimes the sound of their voice.

The beginning rider learns how to mount and dismount, turn, back up, and ride at a walk, trot, and, finally, canter. The English-style rider learns to post a trot—to move up and down in time with the two-beat rhythm of the gait. Both English and Western riders learn to sit a canter.

The advanced English rider may learn the techniques of cueing a horse to perform dressage maneuvers (precision movements) or may learn a specialty such as jumping or riding show horses.

The advanced Western-style rider may learn the special skills involved in working cattle or showing in Western horse show events. One specialty popular among female Western-style riders is barrel-racing, in which contestants are timed as they complete a cloverleaf-shaped course laid out around three barrels.

Various “seats”—positions in the saddle—have been developed for different styles of riding (English or Western) and different types of horses (gaited horses, racers, jumpers, etc.). Most English-style riders in the United States use the balanced, or modified forward, seat—they sit in the middle of the saddle on their pelvic bones with knees bent and feet placed in the stirrups so that their weight is supported on the balls of the feet. They incline the upper body forward as the horse moves, increasing the degree of inclination as the horse moves at a faster pace.

A show seat, saddle seat, or classical seat, in which the rider is more erect and rides with longer stirrups, is used in horse show riding. The jockey, or flat-racing, seat employs stirrups so short that the rider's knees are even with the horse's withers and the rider hunches over the withers and neck. The Western-style rider normally rides erect with longer stirrups than the English-style rider.

The reins are held in either hand or both hands in English-style riding, but in only one hand—usually the left—in Western-style. Western-style riders leave more slack in the reins than is done in most English-style riding.

The rider's hands, legs, weight, and voice are called aids. They help signal the direction, speed, and type of movement the rider wishes the horse to adopt. To make the horse move forward, for example, the rider squeezes the horse with his legs, shifts his weight forward, and loosens the reins. In Western-style riding, the rider turns his horse by neck-reining—moving his hand to one side, so that one rein presses against the side of the horse's neck; the horse turns away from the rein. For some cues the advanced rider may use artificial aids such as spurs or whip. The signals given by an advanced rider on a well-trained horse are so subtle that few observers can detect them.