Three Coat Types
The FCI standard states:

COAT

HAIR : May be smooth, broken or rough.  Must be weatherproof.  Coats should not be altered (stripped out) to appear smooth or broken.

COLOUR : White MUST predominate with black and/or tan markings.  The tan markings can be from the lightest tan to the richest tan (chestnut).
The Russell Terrier comes in three weather resistent haircoats, smooth, broken, and rough. The haircoat must be sufficient for protection underground from roots and rocks. Above ground from brush and rocks. There should be sufficient covering on the under belly for protection with sparse haircoats undesirable. The hair coat of the breed is an important attribute needed for work. The haircoat comes in three types.  Smooth, broken, and rough. The broken coat is a combination of smooth and rough. Stripping should be minimal for exhibition. No one hair coat is preferred over the other.
Tri Colored Smooth Coat
Black & White Broken Coat
Tan & White Rough Coat