The appendix is a small, tube-like structure that is attached to the first part of the colon. When it gets inflamed (often as a result of a blockage), it is known as appendicitis.
Pain in the abdomen (stomach) can be an early symptom of acute appendicitis. The pain may first appear around the belly button and then move to the lower-right area of the abdomen. Surgery is often required to remove the appendix. If treatment is delayed, the appendix can burst, causing infection, or in some cases, even death.
(Click Appendicitis for more information about this topic, including other signs to watch for, how a diagnosis is made, and why not everyone will have the same symptoms.)