*Gastrointestinal tract: esophagus, stomach, and duodenum (esophagogastroduodenoscopy), small intestine (enteroscopy), large intestine/colon (colonoscopy, sigmoidoscopy), bile duct, rectum (rectoscopy), and anus (anoscopy)

*Respiratory tract: nose (rhinoscopy), lower respiratory tract (bronchoscopy)

*Ear: otoscopy

*Urinary tract: cystoscopy

*Female reproductive tract (gynoscopy): Cervix (colposcopy), uterus (hysteroscopy), fallopian tubes (falloposcopy)

*Through a small incision: abdominal or pelvic cavity (laparoscopy), interior of a joint (arthroscopy), organs of the chest (thoracoscopy and mediastinoscopy)