A clear, comprehensive, and rigorous introduction to the theory of computation. What is computable? What leads to efficiency in computation? Computability and Complexity offers a clear, comprehensive, and rigorous introduction to the mathematical study of the capabilities and limitations of computation. Hubie Chen covers the core notions, techniques, methods, and questions of the theory of computation before turning to several advanced topics. Emphasizing intuitive learning and conceptual discussion, this textbook's accessible approach offers a robust foundation for understanding both the reach and restrictions of algorithms and computers. Extensive exercises and diagrams enhance streamlined, student-friendly presentation of mathematically rigorous material Includes thorough treatment of automata theory, computability theory, and complexity theory--including the P versus NP question and the theory of NP-completeness Suitable for undergraduate and graduate students, researchers, and professionals.