A Top view displays the model from the top:
- the xy plane is parallel to your screen (as in a 2D model).
- x is positive from left to right (horizontally).
- y is positive from bottom to top (vertically).
- z is positive toward you, perpendicular to the screen.
While, for a Bottom view:
- y is positive from top to bottom (vertically).
- z is positive away from you, perpendicular to the screen.