Your Skin Is An Organ! The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue guarding the underlying muscles, bones, ligaments and internal organs. The skin is your body’s coat, it protects you and it will help you stay warm when it’s cold and cool when it’s hot. Your epidermis is the top part of your skin and is your body’s largest and fastest-growing organ.