Skin

"The skin is the largest organ of the body, with a total area of about 20 square feet. The skin protects us from microbes and the elements, helps regulate body temperature, and permits the sensations of touch, heat, and cold.
Skin has three layers: The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone.
The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
The deeper subcutaneous tissue (hypodermis) is made of fat and connective tissue.
The skin’s color is created by special cells called melanocytes, which produce the pigment melanin. Melanocytes are located in the epidermis."

Skin Irritation

Skin irritation is the inflammation of the this region of the body usually as a result of a reaction to an allergy or sustained damage to the cell-lining. It can be localized or widespread and depending on the nature of the irritant and/or allergen, as well as the kind of skin, it can also be a one-time occurrence or a repetitive one. However, it is important to note that skin irritation is usually considered to be reversible.