A horse race is a sporting event in which horses compete over an established course to determine the winner. The sport has evolved from a primitive contest of speed and stamina between two animals into a modern spectacle with huge fields, sophisticated electronic monitoring equipment, and immense sums of money at stake. Despite these changes, the basic concept of the race remains unchanged: The horse that finishes first wins.

A thoroughbred, or Thoroughbred, is a breed of horse that has been developed for racing and jumping. The name comes from the word “thorough” and is derived from a description of the type’s long, powerful physique. Thoroughbreds are usually black, brown, or fawn in color, with white markings on the chest and knees. The breed has a history of nearly three centuries.

When a horse enters the starting gate for a race, it is often given a drug called Lasix. The diuretic is used to prevent pulmonary bleeding, which hard running can cause in some horses. Lasix is injected into the horses on race day, and its use is noted in boldface letters in the racing form.

Before the Civil War, most races were match contests between just two horses. As the sport grew in popularity, however, pressure from the public produced events with larger fields of runners. The early 4-mile (6-kilometer) races were run as heats, in which two wins were needed to win. As dash racing became the standard, gaining a few feet in a race gained importance, and the rider’s skill and judgment became crucial.

At the start of a race, a steward or patrol judge, aided by a motion-picture camera, watches to see that all rules are being obeyed. The stewards also take note of the time taken by each horse to cross the finish line. In North America, the finishing time is measured to the nearest one-fifth of a second; in most other countries it is measured to the nearest hundredth of a second.

Once the race is over, a jockey’s winnings are awarded. In addition to the normal prizes for finishing first, second, or third, a rider can bet to win, bet to place, or bet to show. Betting to win is the most risky, but the highest payoffs are awarded for winning. Betting to place and bet to show are lower on average but still offer a good return for your investment.

While horse racing is a multimillion-dollar industry, it is a dangerous sport. Whether because of human error, incompetence, or a combination of factors, the sport is plagued by accidents that result in serious injury or death to horses and spectators. The most infamous incident was the 1978 Santa Anita disaster, in which 19 horses died and 257 were injured. The resulting government inquiry led to the creation of a new oversight authority, the National Thoroughbred Racing Commission. The commission is charged with ensuring the safety of horses, and its members are appointed by the Secretary of State for Agriculture.