The skin is the body's largest organ and is made up of three distinct parts which have distinct functions:

1. Epidermis: Outermost layer of the skin.
   - The stratum corneum which is the most external part of the epidermis acting as a physical barrier.
   - The role of the rest of the epidermis is mostly in the production of the stratum corneum.
2. Dermis: Middle layer
   -Contains the blood vessels to supply the epidermis.
   -Also contains hair follicles, sweat glands and nerve endings.
3. Hypodermis: Deepest layer
   - Thickest part of the skin.
   - Contains fat cells that act as energy reserves and allow the thermal regulation of the body.