Cricket explained

For the uninitiated:

You have two sides, one out in the field and one in. Each man that’s in
the side that’s in goes out, and when he’s out he comes in and the next
man goes in until he’s out. When they are all out, the side that’s out
comes in and the side that’s been in goes out and tries to get those
coming in, out. Sometimes you get men still in and not out. When a man
goes out to go in, the men who are out try to get him out, and when he
is out he goes in and the next man in goes out and goes in. There are
two men called umpires who stay all out all the time and they decide
when the men who are in are out. When both sides have been in and all
the men have been out, and both sides have been out twice after all the
men have been in, including those who are not out, that is the end of
the game!

Source: anonymous forward (obviously through a long chain of not so anonymous sources)