A colonoscopy is a routine procedure designed to allow for visual inspection and evaluation of the interior lining of the colon (large intestine.) Most often, it is used to diagnose colon cancer, check for early warning signs of the disease, and inspect benign or precancerous growths, or polyps.

A video camera mounted on a thin, flexible tube, or colonoscope, is inserted into the rectum and guided through the colon by a gastroenterologist. The colon may be inflated with air prior to the procedure to make viewing and navigating the colon an easier process. A host of instruments can be deployed through the tube, including tools to sample and remove polyps.

Side Note: George W. Bush had a colonoscopy today, and temporarily transferred presidential power to Vice President Cheney for the duration of the procedure and recovery (7:09 to 9:24 a.m EST, 6/29/2002.) Y'know, there's nothing more egalitarian, nothing more noble, nothing more democratic than a president bending over like the rest of us poor saps and taking one for freedom and justice. God Bless the President, and God Bless America, and to the republic for which it stands: one nation, under god, indivisible, with liberty and justice for all!