This book surveys the state of the art in theoretical and computer modeling for biological sciences. Using both mathematical and stochastic computer models of biological systems, the author focuses in particular on three central topics: the origin of life, the immune system, and memory in the brain. Throughout the book, the author emphasizes how the power of modern computers is allowing researchers in theoretical biology to break free of the constraints on modeling that were imposed by the traditional differential equation approach. Unique in its emphasis on modeling and computer simulation, Theoretical Models in Biology: The Origin of Life, the Immune System, and the Brain will be welcomed by students and researchers of mathematical biology.