In the US, we count floors using numbers. The floor of a building sitting at earth level is the first floor. It's the first one you encounter, unless you're in like [[Hong Kong]] or somewhere else that exists on many levels. Europeans call the first floor, the "ground floor," crazy, isn't it? Then, even crazier, if you go up a floor, they call that the "first floor"! Madness. Then the craziness goes up from there.