In meicine, a surgeon is a person who performs surgery. Surgery is a broad category of invasive medical treatment that involves the cutting of a body, whether human or animal, for a specific reason such to remove a diseased organ or to repair a tear or breakage. Surgeons may be medical practitioners, dentists, podiatrists or veterinarians. In earlier times there were also people trained solely in removing bladder stones, but at the present day specialised practitioners would have first been trained in one of the professions already mentioned.