The outermost layer of the epidermis is made up of sheets of dead cells that serve as the major waterpoof barrier to the environment. In addition, special cells called melanocytes inside the epidermis produce brown pigment which helps protect you from ultraviolet light. The middle layer, the dermis, provides a tough, flexible foundation for the epidermis. In the dermis, sweat glands and blood vessels help to regulate body temperature, and nerve endings send the sensations of pain, itching, touch, and temperature to the brain. Oil glands produce a substance called sebum which help to moisturize the skin.
Hair is primarily decorative in humans.
The fat under the dermis provides insulation and helps to store calories.