The coats of domestic dogs are of two versions: "double" being prevalent in dogs (and also wolves) originating from colder climates, made up of the coarse guard hair along with a delicate down hair, or "solitary", With all the topcoat only. Breeds may have an occasional "blaze", stripe, or "star" https://christopherm692uyd9.glifeblog.com/30968168/the-greatest-guide-to-dogs