Butterfly and mushroom. The main difference between the two types is the shape of the popped kernel. Butterfly, or movie theatre style popcorn, is more delicate and is best enjoyed with just simple simple salt, seasoning, or butter.  Mushroom style is perfect to be covered by caramel or other confections. Its' sturdy shape (without those delicate butterfly wings) withstands the process of candy coating. This caramel coverage also protects the popcorn from air which means this popcorn will stay fresh...for a long time.