Horses coat can be any color or length, with any marking.
horses markings sometimes depend on the breed of horse, and sometimes it doesn't. Usually horses who aren't white have white markings. And horses who are white have darker colored markings.
Horses have sleek short hair but in the winter they grow longer hair for warmth. And has to be cut in the spring.
Ponies tend to have longer fur, because most ponies are from colder places.