The nail plate - also known as "Body of Nail" or "Corpus Unguis" - is the actual nail, and is made of a translucent keratin protein composed of amino acids.
The nail fold is the tissue that encloses the nail matrix at the root of the nail. The nail fold attaches the nail to the rest of the skin through the protective cuticle.
The nail matrix is the part where your nails begin to grow. The nail matrix creates new skin cells that push out old dead skin cells to form both finger and toenails.
Shuhak 