“The fancy rat is a domesticated brown rat (Rattus norvegicus), which is the most common type of pet rat. The name fancy rat derives from the idea of animal fancy (promotion of domesticated animals) or the phrase “to fancy” (to like, or appreciate).
Fancy rats have their origins as the targets for blood sport in 18th- and 19th-century Europe. Specially bred as pets since then, fancy rats now come in a wide variety of colors and coat types and are bred and raised by several rat enthusiast groups around the world. Fancy rats are commonly sold as pets in stores and by breeders.
Domesticated rats are physiologically and psychologically different from their wild relatives, and—when acquired from reputable breeders and shops—pose no more of a health risk than other common pets. For example, domesticated brown rats are not considered a disease threat, while exposure to wild rat populations could introduce pathogens like Salmonella into the home. Fancy rats experience different health risks from their wild counterparts, and thus are less likely to succumb to many of the same illnesses as wild rats.
Fancy rats care for themselves, and are thus very affordable compared to even other small pets. This is one of the biggest draws to them. Additionally, fancy rats are quite independent, loyal and easily trained, earning them comparison to both cats and dogs. This comparison is merited given fancy rats are considered more intelligent than any other domesticated rodent.”