The integumentary system, which includes the skin, hair, nails, and glands, serves as the body's largest organ providing protection, temperature regulation, and sensory reception. It consists of two main layers: the epidermis, which is the outer layer, and the dermis, which contains blood vessels and connective tissues. As skin ages, it experiences slower repair, decreased elasticity, and diminished immune response, increasing the risk of skin conditions such as cancer.