The coats of domestic dogs are of two versions: "double" getting widespread in dogs (as well as wolves) originating from colder climates, built up of a coarse guard hair plus a delicate down hair, or "one", With all the topcoat only. Breeds can have an occasional "blaze", stripe, or "star" https://peteru738rzr3.ssnblog.com/31062548/the-definitive-guide-to-dogs