The colon is a long tube-like structure that stores and then eliminates waste material.
Some people develop small bulging sacs pushing outward from the colon wall.
One of these sacs is called a diverticulum. Several of these sacs are called diverticula. The condition of having diverticulum in the colon is called diverticulosis. Diverticulosis can occur throughout the colon but is most common in the left lower part of the colon called the sigmoid colon. The disease is common in the Western world but is extremely rare in areas such as Asia and Africa.