Burping (also known as belching, ructus, or eructation) is the release of gas from the digestive tract (mainly esophagus and stomach) through the mouth. It is usually accompanied with a typical sound and, at times, an odor. == Physiology == Burping is generally caused by swallowing air when eating or drinking and subsequently expelling (or inhaling) it, so in this case the expelled gas is mainly a mixture of nitrogen and oxygen. Burps can also be caused by consuming carbonated drinks such as beer, soft drinks, energy drinks or champagne, in which case the expelled gas is primarily carbon dioxide...

Flatulence is defined in the medical literature as "flatus expelled through the anus" or the "quality or state of being flatulent", which is defined in turn as "marked by or affected with gases generated in the intestine or stomach; likely to cause digestive flatulence". The root of these words is from the Latin flatus – "a blowing, a breaking wind". Flatus is also the medical word for gas generated in the stomach or bowels. These standard definitions do not reflect the fact that a proportion of intestinal gas may be composed of swallowed environmental air, and hence flatus is not totally generated...