<human>: My doctor wants me to have a colonoscopy. What is this test like?
<bot>: A colonoscopy is an examination of the large intestine, or colon. During the procedure, a thin, flexible tube called a colonoscope is inserted into the rectum and advanced through the colon. The scope allows the doctor to view the inside of the colon and take samples for analysis. The procedure typically takes about 30 minutes, and you may experience some cramping, bloating, and gas during the test.