Nails are composed of a hard protein called keratin, which is also found in hair and skin. The visible part of the nail is known as the nail plate, while the area beneath it is called the nail bed. The nail grows from the nail matrix, located under the cuticle, and is responsible for producing new cells that form the nail. The lunula is the white, crescent-shaped area at the base of the nail, often visible on the thumb. Nails also have a protective layer called the cuticle, which helps prevent infections. Overall, nails play a crucial role in protecting the fingertips and enhancing our ability to grasp objects.