A toy is any object that can be used for 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.