A racehorse is a horse specially bred and trained to run as fast as possible in competitions. These horses are athletes, just like human sprinters or marathon runners, and they spend years preparing for races where they compete against other horses.

The most famous racehorses become well known. Secretariat, who won the Triple Crown in 1973, ran so fast that his records still stand today. Seabiscuit, a small horse who became a champion during the Great Depression, inspired many Americans who were struggling through hard times. When a great racehorse wins an important race like the Kentucky Derby, people remember that horse's name for generations.

Racehorses typically start training when they're young, learning to respond to their jockey's commands and building the strength and speed they'll need. Different breeds excel at different types of racing: Thoroughbreds are built for speed over shorter distances, while Arabian horses have stamina for longer races.

Owning and training a racehorse requires dedication and expense. Even so, people have been racing horses for thousands of years, making it one of humanity's oldest sports. The excitement of watching these powerful animals thunder down the track at high speeds keeps the tradition alive.