Skin is the largest organ of the human body, serving as a protective barrier against environmental factors like bacteria, UV radiation, and temperature changes. It is composed of three main layers: the epidermis, dermis, and hypodermis. The epidermis is the outer layer, providing a waterproof barrier, while the dermis contains connective tissue, hair follicles, and sweat glands. The hypodermis, or subcutaneous layer, helps insulate the body and anchors the skin to underlying structures. Skin also plays a vital role in regulating body temperature and enabling the sense of touch. It contains various receptors that respond to pressure, pain, and temperature, allowing us to interact with our environment. Additionally, skin produces melanin, which gives it color and protects against sun damage. Proper skin care is essential for maintaining its health and appearance.