The word „endoscopy“ originates from the Greek language and consists of the prefix „endo“ meaning „within“ and the word „skopein“ which means „to look“. It is an invasive method that involves the use of flexible tube with an attached camera at the tip to observe the interior of organs. Tissue samples that are pathologically altered are collected through a biopsy method and sent for microscopic analysis to establish a diagnosis. In recent times, aside from diagnosis, endoscopy has become increasingly valuable for therapeutic purposes and is applied in many medical branches such as gastroenterology, pulmonology, urology and gynecology. Depending on the organ it is intended for, several types of endoscopic procedures are distinguished in gastroenterology. An esophagogastroduodenoscopy is performed to examine the esophagus, stomach and duodenum, an enteroscopy is performed to examine small intestine, while a colonoscopy is performed to examine the entire colon. With technological advancements, a combination of endoscopic method and ultrasound imaging has resulted in a procedure called endoscopic ultrasound that enables the examination of surrounding structures. For visualizating the bile and pancreatic ducts, a combination of endoscopy and contrast medium is used, know as endoscopic retograde cholangiopancreatography (ERCP). As in all other medical procedures, during endoscopic examinations the nurse / technician plays a crucial role in the psychological and physical preparation of the patient and in collecting the necessary documentation. They are also responsible for preparing the examination room, endoscope and endoscopic equipment. During the procedure itself, they assist the gastroenterologist and, upon completion, ensure proper cleaning, disinfection and sterilization of the instruments. After the examination, they monitor and record the patient's condition and inform the doctor of any deviations from normal.