Colon cancer, also known as colorectal cancer, is a type of cancer that begins in the large intestine (colon). It typically starts as small, noncancerous clumps of cells called polyps that form on the inside of the colon. Over time, some of these polyps can become cancerous. Early detection through screening is crucial for effective treatment and improved outcomes. Symptoms may include changes in bowel habits, rectal bleeding, abdominal discomfort, and unexplained weight loss.