In the human body water is given off by intact skin by evaporation from the epidermis as sweat, a form of cooling in which liquid is actively secreted from sweat glands. Perspiration is the act or process of insensible elimination of fluid through the pores of the skin, which is visible as droplets on the skin. This article describes perspiration, anatomy & composition of sweat glands, different varieties of sweat and its significance in Homoeopathy.