Using parallel machines is difficult because of their inherent complexity and because their architecture changes frequently. This book presents an integrated approach to developing software for parallel machines that addresses software issues and performance issues together. The author describes a methodology for software construction that is architecture-independent and intellectually abstract. The software can execute efficiently on a range of existing and potential hardware configurations. The approach is based on the construction of categorical data types, a generalization of abstract data types, and of objects. This work will be an outstanding reference for researchers in computing.