The American Thoroughbred is a breed of horse known for its speed, agility, and endurance, primarily used in horse racing. Originating in the United States during the 18th century, these horses are descendants of Arabian, Barb, and Turk horses, which were bred with local stock to create a fast and athletic breed. Thoroughbreds are typically tall and slim, with long legs and a deep chest, allowing them to excel on the racetrack. They are recognized for their competitive spirit and are often seen in various equestrian sports, including show jumping and dressage, in addition to racing.