To achieve permanent results in hair removal the hair follicle must be destroyed. The heat of the laser is transmitted through the hair shaft to the deeper part of the body, which requires on the one hand that the wavelength of the laser is in the spectral range that the hair can absorb, and on the other hand that the wavelength of the laser is long enough to penetrate deep into the dermis. So there are various lasers for hair removal but they all have the above two elements, which is the reason why hair removal is more effective on black hair and less effective on blonde and white hair. The epidermis is also pigmented and can absorb light waves just like the hair follicles, so hair removal has the risk of damaging the epidermis, especially in patients with darker skin tones, so patients with lighter skin have a great advantage. Light waves need to pass through the epidermis before reaching the dermis, so epidermal cooling can improve the safety of hair removal and also reduce the pain of hair removal. The jeweled light head of ice point hair removal and the cold gel used for hair removal have this effect. The difference between laser hair removal and photon hair removal is that the laser is relatively more stable and safer in performance, and more efficient and comfortable in hair removal. There are many semiconductor freeze point hair removal available in the market now, making hair removal more popular. Although hair removal is related to the wavelength and performance of the device, it also has a lot to do with the operation of the operator. The operator must be very patient in giving the energy and must carefully observe the skin’s hair response in order to get it just right, destroying the hair follicle without harming the skin. Many patients may be afraid of pain, or the operator may be afraid of damaging the patient’s skin, or the operator may not be patient and careful enough to give enough energy for hair removal. If the hair does not absorb enough energy, the hair will become phototolerant and affect the next treatment, ultimately affecting the effect of permanent hair removal.