How a professional relationship differs from a social relationship?

Think of it this way:

Social relationship is like friends.. you're social. Like when guys get together and watch a football game, shoot some pool, or when women go to clubs or shopping with their friends, that is more of a social relationship.

Professional relationship is more on a mature level. Like you would with your boss/professor/teacher/manager/co-worker. You act classy, well-mannered. Any jokes that would be made would probably not be as funny as it would be with your friends, because of course, it's more of a professional thing.