Re: stringers
Stringers are the "skeleton" of your boat. They are (for lack of a better term) "boards" that run from the bow to the transom giving support to the boat hull structure and to the decking above.
They are sometimes made of wood (picture a 2X6 board running from the transom forward, laying on the 2" side). This is why, when you hit a wave, your boat doesn't fold in half. Sometimes, they are foam or a composite material. They are (or should be) covered with fiberglass to seal water out and to add strength/structure.
If you were to lift the floor out of your boat, you would see them under the floor.
