A horse race is a competitive racing event in which horses compete against each other. It is run over a set distance and is conducted by stewards to determine the winner. The sport is played in many countries around the world.

The first recorded races date back to ancient Greece. They involved both four-hitched chariots and mounted barebacks.

During the seventeenth and eighteenth centuries, races took the form of matches between two horses, with multiple heats and distances varying from two to four miles (3.2-6.4 km). The winning horse would be awarded a purse. The wagering involved was simple and the owners provided the money. Typically, an owner would forfeit half the purse if they backed out of the race.

Today, most horse races involve a fixed distance of between five and six furlongs (one mile). The majority are governed by the rules and regulations of national horse-racing organisations.

Some of the more common types of horse races include handicap, claiming, and starter races. Each has its own unique rules and regulations.

Handicap: A handicap is a competition between horses of similar ages and is based on an adjusted weight allowance. The weights are based on the age of the horse and there are sex allowances for fillies that allow them to carry three to five pounds less than males.

Optional claiming: A claiming race is a type of horse race in which the horses in the field may be entered for a specific claiming price or less. The claiming price is typically lower than the starting price.

Starter: A starter is an official responsible for ensuring that a fair start to the race is achieved. They oversee the loading of horses into the starting gate through a gate crew and have control over opening the gate to begin the race.

Stewards: A steward is an officer in charge of the race and is responsible for enforcing the rules. They have the authority to disqualify a horse or further sanction a rider who they feel has breached the rules.

Photo finish: In the event that a horse is unable to be seen by the naked eye, the stewards will study a photograph of the finish and decide which horse crossed the line first. The stewards will then award the prize to the horse that crossed the line first.

In most countries, betting on horse races is a popular activity for fans. They can place single bets or accumulator bets on different outcomes such as which horse will win the race and which will place.

There are many different types of horse races including flat, steeple chases, hurdle races and jump races. Some of the most famous races include the Kentucky Derby and the Belmont Stakes. The races are contested for prizes of up to $1.5 million.