What is the gutter in bowling?

[answer removed for not follow terms of use]
My answer:
The "gutter" in Bowling, is a term used to describe the two channels, one on either side of the bowling lane. If the bowl reaches the channel, a zero or "miss" is recorded for that shot. Even if the ball comes back out of the gutter at some point, it is still scored as a zero and the pins are reset.