This book provides the basic knowledge necessary to understand the operation of digital computers and also covers topics associated with computer hardware. This book covers the syllabi in the curriculum of various universities in India and abroad. Computer Architecture is concerned with the structure and behavior of the various functional modules of the computer. Computer Organization is concerned with the way the hardware components are connected together to form a computer system. The first edition of the text book was aimed to elucidate the fundamentals of computer organization and architecture.