These are questions that one asks as they visit their physician for their annual exam. A colonoscopy is a test that where the physician looks with a magnifying camera at the inner lining of a person’s large intestine. Sample biopsies may be done at the time of the test. The colonoscopy test is typically performed for colon and rectal cancer screening, but the physician may order it for other reasons as well, which include: blood in the stool, abnormal test results from another colon test, family history of colon cancer, anemia unexplained otherwise. The stated are some indications for colonoscopy, but it is not an inclusive list.