Why do people fart?

People fart mainly because of the gas produced by the intestines.

Farting, also called "exhaust", is a normal physiological phenomenon. When people eat, they produce more gas due to the normal flora in the digestive tract. These gases move downward with the peristalsis of the intestine and are discharged from the anus. When it is discharged, due to the action of anal sphincter, noise sometimes occurs. Therefore, farting is a manifestation of the normal operation of the intestine. On the contrary, if you don't fart, or fart too much and stink, that's an abnormal phenomenon.