Picture of Skin
The skin, the body's largest organ, serves numerous functions, one of which is to act as a protective barrier against the outside world. The skin serves as the first line of defense against infectious agents and substances that may be harmful to the body. Nerves housed in the skin are responsible for the sensations of pain, temperature, and pressure.
The skin is composed of three layers. The outer protective layer, the epidermis, is made up of dead skin cells and pigment-producing cells called melanocytes. Melanocytes produce melanin, a pigment that gives skin its color and helps guard against damage from UV rays. The dermis is the middle layer of the skin. It houses hair follicles, oil and sweat glands, blood vessels, and nerves. The hypodermis is the deepest layer of the skin. It is made of fat that insulates the body and serves as a form of energy storage (calories).
Text Reference: "Structure & Function of Your Skin." American Osteopathic College of Dermatology.