What are human nails made of?

Human nails are made of a tough protein called keratin, which is also present in our hair and skin. Keratin is a fibrous structural protein that forms a protective covering on our nails, providing strength and durability. It is synthesized by specialized cells in the nail bed called keratinocytes, which harden as they grow and push forward, eventually forming the visible part of the nail. Thus, Keratin is the key component responsible for the hardness and rigidity of human nails.