Hair forms in a pouch-like structure below the skin called a hair follicle. What we see as hair is actually the hair shaft, which is the keratinized, hardened tissue that grows from this follicle. The hair root is deep in the skin and this is what the laser targets. The hair root is destroyed or disabled by sending a beam of light to a group of hair follicles for a millisecond. The laser beam finds the hair follicles by targeting the melanin, the substance giving skin and hair the dark color. The light energy is absorbed by the pigment in the hair follicle and the hair shaft, with no harm to the skin. The surrounding skin may be protected by a gel, spray or cooled tip pressed against the skin. Because not all the hair in a treated area may be in the active growth stage, more than one treatment is usually necessary to remove hair that subsequently enters the growth phase. 90% of people who undergo laser hair removal have permanent hair loss.