عرق (sweat) is a clear, salty liquid produced by the sweat glands in the skin. It plays a crucial role in regulating body temperature through the process of evaporation. When the body heats up, sweat is released onto the skin's surface, cooling the body as it evaporates. Sweat is composed mainly of water, but it also contains small amounts of salts, urea, and other substances. The amount and composition of sweat can vary based on factors such as exercise, temperature, and individual health. Sweating is a natural response to heat and physical activity, helping to maintain homeostasis.