An endoscopy (looking inside) is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. There are many types of endoscopies. Depending on the site in the body and type of procedure, an endoscopy is performed by an endoscopist who is typically either a doctor or a surgeon. A patient may be fully conscious or anaesthetised during the procedure. Most often, the term endoscopy is used to refer to an examination of the upper part of the gastrointestinal tract, known as an esophagogastroduodenoscopy