Imagine you are programming in a computer which has no "PLAY" key and you want to create an event triggered by the "PLAY" key in a TV.
You need to know the keycode for "PLAY".
Anyway, a keycode list in the manual entry for the keyboard object would be nice.
Also, some special info on keycodes for non-standard entries should be nice, too. Such as "The ok button on remotes sends ENTER".