Fox Terrier usually means the Smooth Fox Terrier or the Wire Fox Terrier, two closely related breeds that share a build and a personality but differ in coat. They were developed in Britain to bolt foxes from their dens during mounted hunts, and their mostly white coats kept riders and hounds from mistaking them for quarry. The Toy Fox Terrier is a separate, much smaller breed, and some terrier mixes are listed under the same name.
Most weigh 15 to 19 pounds and live 12 to 15 years. Expect a quick, funny dog with a mind of its own and a need for training that stays interesting. Coat matters for planning: a Smooth needs a weekly brushing, while a Wire sheds little but needs regular clipping or hand-stripping. Dogs vary, so judge the dog in front of you, not just the breed.