The intestine is a long, coiled tube that starts at the stomach and ends at the anus. It is divided into two parts: the small intestine and the large intestine. The small intestine is about 20 feet (6 meters) long and has three parts: the duodenum, jejunum, and ileum. The large intestine is about 5 feet (1.5 meters) long and has four parts: the cecum, colon, rectum, and anal canal.
The main function of the intestine is to absorb nutrients from food and get rid of wastes. The intestines are lined with tiny finger-like projections called villi that increase the surface area for absorption. The intestines also have bacteria that help break down food.
The small intestine absorbs most of the nutrients from food, including carbohydrates, fats, proteins, vitamins, and minerals. The large intestine absorbs water from wastes and some vitamins made by bacteria in the gut. Wastes that are not absorbed become stool or solid waste which passes through to the rectum and out of the body through the anus as a bowel movement.