Ulcerative colitis is a type of inflammatory bowel disease that affects the colon and rectum. It causes inflammation and ulcers in the lining of the digestive tract, leading to symptoms like abdominal pain, diarrhea (sometimes with blood), urgency to go to the bathroom, and fatigue. The exact cause is unknown, but it's thought to involve a combination of genetic, environmental, and immune system factors. Treatment focuses on reducing inflammation and managing symptoms with medication, diet changes, and sometimes surgery. With proper care, many people with ulcerative colitis can lead normal lives.