The primary function of the skin is for protection of your body from harmful and potentially fatal infections. Therefore the best protection your body has from infection is healthy intact skin. Broken skin or skin that has injuries leaves your body open to infectious agents. Your skin is comprised of specific layers and each layer has a function in the total infection control for your body.
Did you also know that every one of us has a colony of staff bacteria that reside on every inch of our skin? This is called colonization, and every persons unique staff infestation is slightly different from anyone else. This is why when you get a small cut it often becomes reddish and irritated looking right before it heals... You have a Staff war going on! Some other staff bacteria is trying to gain entry into your body and your own staff is on the defensive fighting it off for you so that you can not get sick unless your immune system has been compromised.
Diseases or disorders of the skin (such as acne or cancer) are diagnosed and treated by a dermatologist. And you thought all they did was plastic surgery! A Dermatologist can go into a variety of fields such as cosmetic surgery, skin cancer, and even specialize in various diseases and disorders of the skin. They study the structure and function of the skin as well as how the skin protects us from a multitude of infectious agents. Some Dermatologists may study the direct relationship between skin diseases and how they interact and affect other organs in the body.