In the clinic, warts are caused by human papilloma virus infection, and a common benign epidermal abnormalities. The so-called freezing method of wart removal is to apply liquid nitrogen spray to the surface of the patient’s wart. After a few days, the wart can slowly dry out and fall off, and a crust will appear, which is the method of removing the wart. Other methods such as laser and electrocautery are used to cause the warts to necrotize and fall off in a different way.