Any 3-dimensional object can be represented by it’s projections on parallel planes. They constitute the front view, top view (and some times the side view). This is the simplest of the available techniques and can be done quite rapidly and also with reasonable accuracy. But the views will be useful only to trained engineers and architects whereas a common viewer may not be able to make much out of it.
For example if a motor car is represented by what it looks like from the front, from the side and from the top, a trained engineer or mechanic can immediately visualize it’s form, including the various dimensions. But a common man cannot make any thing out of it. Thus, this method may be useful in applications like CAD, but is useless as far as animation or simulation is concerned.
