Since there are similarities between the process of writing computer programs and the process of writing successful expository prose, a student's knowledge of computer programing can contribute to the understanding of some principles of composition. The establishment of a clear objective is the first priority of both the writer and the programer, who must then separate the problem into its parts and discover the relationship between these parts. Then the individual steps necessary to realize the various parts of the outline or flowchart must be constructed. In the cases of both writing and programing, the constraints imposed by the audience--the reader or the computer--on the finished product are the same (although different in degree). Thus, because computers demand explicit step-by-step instructions, computer programers are forced into deliberate planning, clear and coherent thought, and explicit expression. Such valuable habits are easily transferable to the composing process. A computer program may also be viewed as a system of parts that solve a problem. An essay is a similar problem solving system, with the problem being the elucidation of the thesis statement. If students can be shown that an essay, like a program, is a system, they then have at their disposal a set of attitudes and concepts for understanding the composing process. (HOD)