In the fabrication and manufacturing world, it is often smart to make a model of something before laying out the time and cost to build the actual unit. In days past, this meant creating a scaled-down replica of the finished piece. This was just as labor-intensive as building the full-sized version, and the entire model would have to be scrapped if design modifications were necessary.

Things are much easier today. It is possible to create a 3D modle of a product electronically. All parts fit together just as they would in a physical model. It is possible to rotate the model, zoom in to see the finest detail, and view its components in layers that can be peeled-back one at a time. It is often almost impossible to tell a 3D model from the real thing.

The problem has been the cost of the sophisticated software required to do this. Rhinoceros NURBS modeling for Windows offers this amazing capability at a small fraction of the price of competing programs, It is easy to learn, and comes with comprehensive tutorials.