/bə-fər ō-vər-ˈflō/
n. What happens when you try to stuff more data into a buffer (holding area) than it can handle. This may be due to a mismatch in the processing rates of the producing and consuming processes (see overrun), or because the buffer is simply too small to hold all the data that must accumulate before a piece of it can be processed. For example, in a text-processing tool that crunches a line at a time, a short line buffer can result in lossage as input from a long line overflows the buffer and trashes data beyond it. Good defensive programming would check for overflow on each character and stop accepting data when the buffer is full up. The term is used often by humans in a metaphorical sense.
"What time did I agree to meet you? My buffer must have overflowed." Or "If I answer that phone my buffer is going to overflow."
See also spam, overrun screw.