A hands-on approach to understanding and building compilers using the programming language Python. Compilers are notoriously difficult programs to teach and understand. Most books about compilers dedicate one chapter to each progressive stage, a structure that hides how language features motivate design choices. By contrast, this textbook provides an incremental approach that allows students to write every single line of code themselves. Jeremy Siek guides the reader in constructing their own compiler in the powerful object-oriented programming language Python, adding complex language features as the book progresses. Essentials of Compilation explains the essential concepts, algorithms, and data structures that underlie modern compilers and lays the groundwork for future study of advanced topics. Already in wide use by students and professionals alike, this rigorous but accessible book invites readers to learn by doing. Deconstructs the challenge of compiler construction into bite-sized pieces Enhances learning by connecting language features to compiler design choices Develops understanding of how programs are mapped onto computer hardware Classroom-tested, hands-on approach suitable for students and professionals Extensive ancillary resources include source code and solutions