The skin has an important role to play in the fluid and temperature regulation of the body. If enough skin area is injured, the ability to maintain that control can be lost. The skin also acts as a protective barrier against the bacteria and viruses that inhabit the world outside the body.
The anatomy of the skin is complex, and there are many structures within the layers of the skin. There are three layers:
Epidermis, the outer layer of the skin
Dermis, made up of collagen and elastic fibers and where nerves, blood vessels, sweat glands, and hair follicles reside.
Hypodermis or subcutaneous tissue, where larger blood vessels and nerves are located. This is the layer of tissue that is most important in temperature regulation.
The amount of damage that a burn can cause depends upon the type of burn, its location, its depth, and how much body surface area that it involves.