The integumentary system consists of the skin, hair, and nails. It protects the body from damage, infection, dehydration, and temperature changes. The skin has three layers - the epidermis, dermis, and subcutaneous layer. The epidermis contains no blood vessels and is made of keratin. The dermis contains hair follicles, glands, blood vessels, and nerves. The subcutaneous layer stores fat. Burns are classified as first, second, or third degree depending on the depth of skin damage. Their treatment ranges from creams for mild burns to skin grafts for severe third degree burns. Surgical procedures and medications are used to treat various skin conditions.