What are you trying to do? Detect browser zoom? Be aware that zoom can be changed in the menu in which case the event won’t be triggered.
There are 3 key events: keydown, keypress and keyup. `keypress` is special because it is only triggered for keys and key combinations which can insert characters (I’m simplifying of course) and sets `e.which` to the ascii code of the pressed letter instead of the key code. I think that’s becuase it’s main use is to capture user input.