An endoscope is a device consisting of a tube and an optical system. In endoscopy, this device is introduced through the mouth or anus to view the interior of the body.

How is an endoscopy test performed:
Endoscopes used to look directly at the outside of the uterus, Fallopian tubes, ovaries, appendix, and other abdominal organs have the special name laparoscope.

Other endoscopes are inserted through incisions to look at joints (arthroscopy), and still others to view the inside of the bladder (cystoscopy).