Considered an esoteric area of computer science until recently, finite state techniques are finding a growing number of applications, from genomics to speech recognition. Yet the field's body of knowledge remains scattered among various domains, such as computational linguistics, hardware design, and simulation engineering, to name just a few. The Handbook of Finite State Techniques unifies and codifies the body of knowledge. In chapters contributed by top experts in finite automata, regular expressions, transducers, and state machines, it builds a solid background in the theory and algorithmics, then explores each of its application domains. Source code is provided for download and noncommercial use.