There are many causes of hemorrhoids, mainly three: 1, dietary habits: over-eating spicy food, cold, greasy, and irritating food; 2, bowel habits: prolonged bowel movements and long squatting time can cause hemorrhoids; 3, physiological anatomical structure: because hemorrhoids develop at the end of the rectum, the overall structure of the end of the rectum does not have a venous valve, which can easily cause venous stasis and cause hemorrhoids. In addition, hemorrhoids are classified according to their anatomical structure, the dentate line, including mixed hemorrhoids, external hemorrhoids, and internal hemorrhoids. Hemorrhoids above the dentate line are called internal hemorrhoids, while those below the dentate line are called external hemorrhoids, and internal and external hemorrhoids that fuse together in the same area are called mixed hemorrhoids.