A small
mammal belonging to the genus
Mustela of the the
weasel family. Often kept as a pet. Ferrets were first
domesticated from the
European polecat around 3000 years ago in ancient
Egypt, and modern domestic ferrets are not known to be able to survive outside
captivity.
Ferrets are very inquisitive and playful, and make wonderful pets. Every ferret has a distinct personality. They are generally indoors-only; if let outside, they should be kept on a leash or they might get into trouble (ferrets are very good at getting into trouble). Also, if you're going to have a ferret in your home, you'll probably want to ferret-proof it first.
Contrary to some reports, ferrets are not known to get rabies with any frequency. If you worry about this sort of thing, though, there is a rabies vaccine approved for use on ferrets. They are also not vicious and don't usually attack pet birds or children, unless they're jealous. Your modern ferret probably wouldn't know what to do with a rabbit if it saw one (in fact, some people keep ferrets and rabbits together without problems).
Ferrets are illegal in some unenlightened locations, including the state of California. This is probably due to ignorance and/or bureaucratic incompetence.
The domestic ferret should not be confused with the black-footed ferret, which is an endangered species native to North America. The ferrets kept as pets are not endangered.
Some information in this wu comes from Encyclopedia Britanica and Pets Magazine.