Digestive diseases include a wide spectrum of disorders affecting the oropharynx and alimentary canal, liver and biliary system, and pancreas. These disorders have diverse causes, including congenital and genetic anomalies, acute and chronic infections, cancer, adverse effects of drugs and toxins, and, in many cases, unknown causes. Some conditions, such as foodborne diarrheal diseases, are so common as to be considered a universal life experience, while many others are relatively uncommon or rare. The impact of these diseases ranges from the inconvenience of a transient diarrheal disease causing missed time from school or work, to chronic and debilitating illnesses requiring continuous medical care, or, all too frequently, to dreaded conditions such as pancreatic cancer that are usually fatal.