The term 2D screen is only used to contrast the 2D ... See virtual reality. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.

Drawing programs and 2D CAD programs allow objects to be drawn ... See graphics and 3D graphics. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.

The surface of the sphere and the plane are two possible 2D spaces, meaning you can walk in two directions: north and south or east and west. What other possible spaces might you be living on? That is ...