Orthographic Projections

Here you can find an example. I have used these colours on purpose.

Yellow= FRONT ELEVATION

Magenta= SIDE ELEVATION

Cyan=PLAN VIEW

Here you have a presentation where you can find a good explanation of the way we can get Ortographic Views  of a solid.
Bellow you can find an interactive GeoGebra´s Applet to play with and to easily get to understand how this system works.




This website will help you improve your spatial vision.

SKETCHUP AND ISOMETRIC PERSPECTIVE

How to use SketchUp to get a 3D solid