The art of good programming depends upon the discipline of the programmer, no matter what language is being used. The purpose of object oriented programming (OOP) is to produce well designed reusable code. In principle OOP can be done in any language, even assembly. This is because all OO language compilers/assemblers (e.g. C++) ultimately translate the high level constructs of the language into machine language. Thus there is a mapping from an object oriented semantics onto the instruction and data arrays that are executable images.

Here we will present a design and implementation method for producing OO code in the C language. It turns out that using this methodology will strongly improve your overall program design and implementation just as you expect when programming in a native OO language like Java or C++. When working in C, however, the discipline applied to producing good designs comes from the programmer and not from the language itself.