Bahahah good try chirone...dont read a map then LOL. Maps work in Easting and Northing...which are X and Y respectively.....which are the same as a graph dango. So as you look at the plan/map from top view X (East) and Y (North) are relative to the ground plane...Z (Height) was then utilised for RL's and contour levels etc.

CAD programs seem to have adopted this axis rotation for 3D...if you look at the ortho front view in Maya this seems to be the base for the orientation. If you place this on a sphere (the Earth) then Y can never be up....it will always correlate with a longitude and X with latitude.

I do find it strange though...as most plans start in a top view...which would be X and Y....I wonder what made the developers choose this way for CAD. I know a math orientation is different too...where we have 0°(Y) at the top and 90°(X) to the right and math has 0° on X...this I cant remember maybe ct will know that one.

Buy yourself a Tom Tom kids...then you wont get lost...just drive into the bush cos the road aint built...damn Surveyors bahahaha