Structure of the nails
Fingernails and toenails are made from skin cells. Structures that are made from skin cells are called skin appendages. Hairs are also skin appendages.
The part that we call the nail is technically known as the “nail plate.” The nail plate is mostly made of a hard substance called keratin. It is about half a millimeter thick and slightly curved.
The nail is firmly attached to the nail bed beneath it. The nail and nail bed separate at the tip of the finger or toe, where the end of the nail sticks out. This allows us to use our nails as tools, for example for scratching. The nails are also an important part of the sense of touch.
The nail is framed by the lateral nail folds on the left and right side of it. The skin bordering the lower end of the nail is called the proximal nail fold. A thin layer of skin, known as the cuticle, grows over the nail there.