Inflammatory Bowel Disease (IBD) is a chronic inflammatory condition affecting the gastrointestinal tract. The two main types of IBD are Crohn's disease and ulcerative colitis. - Crohn's disease can affect any part of the digestive tract from the mouth to the anus, but it most commonly affects the small intestine and the beginning of the large intestine. - Ulcerative colitis affects only the large intestine (colon and rectum). Both conditions primarily cause inflammation, pain, and other symptoms related to the intestines.