The Essentials of Computer Organization and Architecture was written to provide a textbook that incorporated all of the necessary organization and architecture topics, yet was concise enough to allow the material to be covered in one semester. This book covers all the core topics, including digital logic, data representation, machine-level language, general organization, assembly language programming, CPU organization, memory organization and input/output devices. The goal of The Essentials of Computer Organization Architecture is to allow the students to tie the hardware knowledge covered in this book to the concepts learned in their introductory programming classes to give a complete and thorough picture of how hardware and software fit together.