Design includes all activities involved from the original concept to the finished product. Design is the process by which products are created and modified. For many years designers sought ways to describe and analyze three-dimensional designs without building physical models. Although orthographic projections can be used to provide much of the information, they still require designers to translate between the three-dimensional object and flat two-dimensional views. With the advancements in computer technology, the creation of three-dimensional models on computers offers a wide range of benefits. Computer models are easier to interpret and can be altered easily. Computer models can be analyzed using finite element analysis software, and simulation of real-life loads can be applied to the computer models and the results graphically displayed.

There are three basic types of three-dimensional computer geometric modeling methods: wireframe modeling, surface modeling and solid modeling. The 3-D wireframe models contain information about the locations of all the points and edges in space coordinates. The 3-D models can be viewed from any direction as needed and are reasonably good representations of 3-D objects. But because surface definition is not part of a wireframe model, all wireframe images have the inherent problem of ambiguity.

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