The set of rules and methods which describe the organization, functionality and implementation of computer systems are known as computer architecture. It is a sub-field of computer engineering. The primary goal of computer architecture is to design a computer which maximizes performance while keeping power consumption in check. It should also keep the costs low compared to the amount of expected performance and should be very reliable. There are three main subcategories within this field. These are instruction set architecture (ISA), microarchitecture and system design. The machine code which a processor reads and acts upon is defined by ISA. Microarchitecture details how a particular processor should implement the ISA. The rest of the hardware components which are in a computing system are included in system design. Computer architecture is an upcoming field of computer engineering that has undergone rapid development over the past few decades. This book is compiled in such a manner, that it will provide in-depth knowledge about the theory and applications of this field. Those in search of information to further their knowledge will be greatly assisted by this book.