Fiber stomach, duodenoscopy, and gastroscope are the most widely used endoscopes in clinical practice. Metal hard tubular colonoscopy, also known as sigmoidoscopy, is commonly used for the examination of sigmoid colon and rectal lesions, or for specimens or pathogens. Before the examination, the patient needs to clean the enema and check it at the knee elbow. The shape of the fiber colonoscope is the same as that of the fiber endoscope. It has three specifications: long, medium and short. Endoscopes used in the respiratory system include bronchoscopes, thoracoscopes, and mediastinoscopes. Metal hard tube bronchoscopes are only used for the removal of foreign bodies in children's trachea. The widely used fiberoptic bronchoscope is similar in appearance to a fiberscope, but the body is short. Except for severe cardiopulmonary dysfunction, most people can do this test, which is a simple and safe method for the diagnosis and treatment of bronchial, pulmonary, and pleural diseases. The positive rate of diagnosis of lung cancer is higher. The positive rate of diagnosis of tuberculosis, especially endobronchial tuberculosis, is higher. Can also be used to rescue critically ill patients. Thoracoscopy is used to diagnose chest and lung disorders. The endoscope is placed in the urinary system (bladder, ureter, renal pelvis) to diagnose and treat urinary diseases. The hysteroscopy is a metal hard tube type. The examinee removes the bladder and takes the lithotomy position. No anesthesia is required. Those with mental stress can be intramuscularly injected with sedatives before surgery. Laparoscopy is mostly metal hard tube type and must be used under aseptic conditions to avoid abdominal infection. Ophthalmoscope, also known as ophthalmoscope, in addition to direct observation of the optic nerve, retina and other lesions, can also determine the degree of hypertension, arteriosclerosis through the changes of fundus blood vessels, and determine the cerebral edema according to the optic nerve head edema.