Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, to help improve bodily function or appearance or to repair unwanted ruptured areas. The patient or subject on which the surgery is performed can be a person or an animal. A surgeon is a person who practices surgery and a surgeon's assistant is a person who practices surgical assistance. A surgical team is made up of surgeon, surgeon's assistant, anesthesia provider, circulating nurse and surgical technologist. Surgery usually spans minutes to hours, but it is typically not an ongoing or periodic type of treatment

The term "surgery" can also refer to the place where surgery is performed, or simply the office of a physician, dentist, or veterinarian.