The Ideal "Puna" House Design

[MarkP]

I have seen many houses in Hawaii that were built high up with a space underneath. Does anyone know why? I have seen it done where it was the easiest way to deal with the slope of the ground, so one side winds up being quite high off the ground while the other side is only a couple of feet, but I have also seen houses that were much higher than necessary to deal with the slope.