What is the appendix for

Ten years ago, this question would have received the stock answer: I don't know. While clearly a part of the digestive system, as it is attached to the large intestine right where that component of the digestive system meets the much longer small intestine (the distinction between "large" and "small" in this particular context refers to the respective diameters of the two organs), the function of the appendix remained a mystery until very recently. Other than the fact that, in many people, it eventually becomes inflamed and must be removed lest it burst (a process known as "peritonitis" with potentially fatal implications) it had been written off as a basically useless part of human anatomy. As of the past decade, however, researchers have discovered the appendix's main function, which, appropriately enough, is tied to the digestive process. It has long been known that the digestive system utilizes certain "good" bacteria, the presence of which is essential to a healthy, fully-functioning system. What wasn't known until 2007, however, is that the appendix serves the important function of regenerating the body's supply of "good" bacteria when that supply is depleted due to illness. The answer to the question, then, is that the appendix produces bacteria important to the digestive process.