This text uses chaos theory and nonlinear dynamic systems to explain specific physical phenomena, both intrinsic to the materials used, and caused by external factors. The author observed and reported on chaos in semiconductors in 1982. This book teaches the reader how to use chaos theory to understand and model nonlinear carrier dynamics in semiconductors. It sets out the historical background and addresses existing and emerging challenges. It concludes with a description of typical behaviours observed in different types of semiconductor material.