Said by Hank and his friends while drinking beer, it is usually a term showing satisfaction.
Usually said by Kahn and his family to Hank and his family, it is a term referring to people of mountainous areas. In the show, it may mean something along the lines of "stupid hicks."
Also used as an offensive remark by Kahn and his family, it is used in the same way as "hillbilly," although they mean different things.
A universal term referring to people of the New England states, though in the show, it is mostly referred to people of New York.