It's one of the classifications for the breed groups. According to the book that I have in my lap they are the group of dogs that has had a more influential relationship with humans. They're breeds that evolved in the artic regions of of the world. It's got breeds like Malamutes, Papillon, Pom's, Akita's basicly it's the more head strong working breeds, they usually have a tail that curls up over their backs because of the parts of the world where they were developed.