A yearling is a young animal, typically a horse, that is between one and two years old. This stage of development is crucial as yearlings undergo significant growth and begin to develop their physical and social skills. They are often weaned from their mothers and start to adapt to life without parental care. In the context of horse racing, yearlings are often sold at auctions, where buyers look for promising young horses to train for future competitions. Proper care and training during this period can greatly influence their performance as they mature into adult horses.