Colitis is the term for inflammation of the colon or large bowel or intestine.
The rectum is the very last part of the colon. When it is inflamed the term
proctitis is used. Understanding the causes and treatment of colitis requires a
basic understanding of the colon and inflammation.

The beginning of the colon is called the cecum. It begins in the lower right
portion of the abdomen where the last part of the small intestine (ileum)
empties into the large intestine. This part of the colon is also where the
appendix attaches. The segments of the colon in order from the beginning of the
colon or cecum going distally are ascending, transverse, descending, sigmoid
colon and rectum. One of the major jobs of the colon is to recycle water for the
body. When the entire colon is present and healthy the stools have only enough
water in them to remain soft and easy to pass, but not so watery or loose that
leakage occurs and dehydration ensues. When a large part of the colon is removed
or when the colon is significantly injured the stools are very watery and
frequent.

Inflammation is the body