Pet

A pet or companion animal is a domesticated animal that is kept by humans for companionship or for the beauty of its appearance or utterances, rather than for economic reasons.

While in theory one could keep a blue whale as a pet, in practice a small number of species of mammals and birds have dominated the pet scene for a very long time. Fish have joined them more recently. With the exception of iguanas and non-venomous snakes, few reptiles and amphibians make good pets.