While there are many methods to eliminate unwanted hair, very few can eliminate hair regrowth while leaving the surrounding skin undamaged. Lasers and other light modalities use the principle of selective photothermolysis to eliminate hair and its potential regrowth without damaging the surrounding skin. During a laser hair removal treatment, light passes through the skin and is absorbed by melanin in the hair shaft. This raises the temperature of the hair follicle and thermally destroys the cells responsible for regrowth. Optimal settings (wavelength, pulse duration and power) are chosen to ensure damage to these cells and not to the rest of the skin.