Written by a chemical engineer rather than by a computer scientist, this book fills the gap between texts which teach computer languages or programming methods and chemical engineering texts which omit details of writing programs. In order to write a computer program and get it to work, general theoretical principles are not enough; one has to actually do the job. This is done in each case by first taking the reader through a manual calculation, then presenting a computer program to perform the same task. Explanation of how the program operates is given in some detail. Topics discussed in this way include: computer flowsheeting; interpretation and accessing of results and physical data; forward feed multi-effect evaporation; binary distillation; linear programming; introduction to finite differences with simple heat exchanger example; steady state multi-dimensional heat conduction; unsteady state heat conduction; solution of automatic control problems using finite differences. In each case, the necessary theory is fully introduced. The programs are written in BASIC - an easily learnt, moderately powerful language available on both mainframe and desk-top computers