Box style boards
Box Style Cornhole Boards are those characterized by having enclosed sides, given them a boxed look. In contrast to most boards which are framed by 2x4's, the box style boards are usually made entirely of plywood. Sometimes the sides will have a slight arc to them, so the entire side does not rest on the ground.
Box style boards are a much less popular style of cornhole boards. While they are incredibly sturdy, and generally don't have any moving parts, they are also very bulky. Most box style boards are more difficult to transport, because they can't be broken down.