How does the built-in limiter work?

In the docs for set_mixer_control! there is an option to ‘bypass the final limiter’

What does the built-in limiter do? Does it cap the combined output to 0db no matter what?

EDIT: I’m asking because I’m creating a piece with a lot of randomness and I’m wondering if I should stick a compressor on the main outs to act as a limiter