Foundations of ComputerScience signals a significant new advance in the way the fundamentals of computer science theory are taught. Written for those already familiar with programming, Aho and Ullman's innovative textbook skillfully integrates the discrete mathematics computer science students need to know with the models, concepts, and techniques of the field. Bv combining the foundations with the computing, the book stands as a single authoritative resource on the theoretical essentials of computer science, clearly demonstrating how mathematical abstructions become working programs.