A laryngoscope is used to obtain a view of the glottis, the middle part of the larynx, the area where the vocal cords are located. It consists of a handle with a battery, and a blade with a light source. Laryngoscopy is done with the patient lying on his or her back: the laryngoscope is inserted into the mouth to push away the tongue and lift the epiglottis, the flap that covers the air passage while swallowing, so that a view of the glottis is possible. The procedure is most often employed in tracheal intubation (inserting tubes into a patients airway in order to link them to an artificial respirator), an extremely uncomfortable procedure not usually performed on conscious patients.