Stan Marsh - Reasonably sane and normal, Stan is the leader of the kids and usually the voice of reason.

Kyle Broslofski - Kyle is a fairly neurotic kid from a Jewish family, but is otherwise fairly normal.

Kenny McCormick - Kenny comes from an extremely poor family,and has to make up for his low social class by being the most foul-mouthed kid of the group.

Eric Cartman - Cartman is fat and sensitive about it, mostly because he comes from an extremely dysfunctional home.