The largest organ in the human body is the skin. It serves several essential functions, including protection against environmental hazards, regulation of body temperature, and sensory perception. The skin is comprised of multiple layers, such as the epidermis and dermis, which contain various structures like hair follicles, sweat glands, and nerve endings. Additionally, the skin plays a crucial role in vitamin D synthesis when exposed to sunlight, highlighting its importance in overall health and well-being.