Piebald

Piebald is the typical patched appearance seen in many dogs. The pattern goes under several names, common ones can be pinto, splash or bicolour. The patches appear randomly, in shape, size and quantity, but it appears to be somewhat possible to specifically breed for shape of patches since some breeds often have similar markings (for instance many english springer spaniels have a mantle-like pattern, japanese terriers often have certain body patches etc). There will normally be colour on the base of the tail and head (the head is usually solid coloured, with a white muzzle and blaze, though there are exceptions). 

Piebald brittany. This dog also shows roaning of the white areas.

Liver red nova scotia duck tolling retriever