Hair and nails are modifications of the skin consisting of protein filaments. They are both composed of keratin, a fibrous structural protein. Hair is found on most of the body, except for the palms of the hands and soles of the feet. Nails are found on the fingers and toes.
Hair and nails play an important role in protection and sensation. Hair helps to protect the body from heat loss, UV radiation, and physical damage. Nails help to protect the fingertips and toes from injury. Both hair and nails also contain nerve endings, which allow us to feel sensations such as touch, pressure, and pain.