A toy is anything that can be used in play. Toys are usually associated with children and pets, but it is not unusual for adults and some other animals to play with toys. An example of this is a dolphin being trained to nudge a ball through a hoop. Many items are designed to serve as toys, but goods produced for other purposes can also be used. For instance, a small child may pick up a household item and "fly" it through the air as to pretend that it is an airplane. Or, an animal might play with a pinecone by batting at it, biting it, chasing it, or by tossing it around. Another consideration is interactive digital entertainment, such as a video game. Some toys are produced primarily as collector's items and are intended for display only.

The origin of toys is prehistoric; dolls representing infants, animals, and soldiers, as well as representations of tools used by adults are readily found at archaeological sites. The origin of the word "toy" is unknown, but it is believed that it was first used in the 14th century.

Toys, and play in general, are important when it comes to growing up and learning about the world around us. The young use toys and play to discover their identity, help their bodies grow strong, learn cause and effect, explore relationships, and practice skills they will need as adults. Adults use toys and play to form and strengthen social bonds, teach, remember and reinforce lessons from their youth, discover their identity, exercise their minds and bodies, explore relationships, practice skills, and decorate their living spaces.