A horse race is a contest of speed or stamina between two or more horses on a race track. Over the centuries horse racing has evolved from a primitive contest between two animals into a massive entertainment industry, but its basic concept has remained the same: the first animal to cross the finish line is declared the winner. In modern times horse races involve thousands of entrants and sophisticated electronic monitoring equipment, but the basic rules of the sport have not changed significantly.

Although national horse-racing organizations may differ in their rulebooks, the vast majority are based on a version of the British rulebook compiled in the 18th century by Colonel Richard Nicolls. Nicolls is credited with introducing organized horse racing to the United States. In early horse races, bets were placed to win only; in modern times bettors often wager on the winner and the top three horses (win, place, and show). The process of accepting bets was extended from private bets to bookmaking in the 19th century, where bettors share in a pool of money won by all the winners, minus a percentage for the track management.

Horses are trained and conditioned to run in races on a variety of surfaces, including dirt, grass, and synthetic turf. Some of the oldest and most famous race tracks are in Ireland, where horse breeding has long been a staple of the economy. The Irish breed the best thoroughbreds in the world, and their horses have won countless international races. Man o’ War, the winner of the fourth Triple Crown in 1937, and Seabiscuit, the grandson of Man o’ War, are among the most famous Thoroughbreds ever to race.

The sport of horse racing began in the 17th century in England and France, and it spread to other countries as horses were imported and exported for training and boarding. The sport became popular in the United States after the Civil War, when American soldiers who had been trained in England brought the idea to America.

There are several different types of horse races, but the most common is a flat race in which a horse competes on an oval course over distances from 440 yards (400 m) to two miles or more. Shorter races are called sprints, while longer distances are known as routes.

Handicap: A race in which the racing secretary assigns weight allowances designed to equalize the chances of winning by comparing each entrant’s past performance with that of the other horses in the race. The entrants must be classified by age; two-year-olds, for example, carry less weight than three-year-olds. In some cases, sex allowances are also provided; fillies carry lower weight than males.

A horse can be ridden by either a professional jockey or a nonprofessional rider. The former is usually the more experienced rider. The latter is referred to as an apprentice jockey and is usually a student. An apprentice jockey can be a man or a woman. In a hand ride, the jockey urges the horse on by “scrubbing” his or her hand up and down the horse’s neck, and the horse is not whipped during a race.