The fancy rat or pet rat is a type of the brown rat ("Rattus norvegicus") that is bred to be a pet. The name "fancy rat" has nothing to do with the "fanciness" of how they look. It comes from the phrase "animal fancy". A person who keeps pet rats is said to be involved in "rat fancy." Some people domesticate black rats ("Rattus rattus"), and Gambian pouched rats ("Cricetomys gambianus"). These types of rats are not usually called fancy rats because the hobby does not center around them.