This book describes, in easy language, building blocks for computer, register transfer language and architecture of a simple processor. CPU Organization, Assembly language programs and Arithmetic algorithms are all explained in such a manner, that students of all streams can understand technical subjects very easily.Special features of the book are:Combinational circuits, Sequential circuits, registers, counters, etc. are explained in detail for building strong fundamentals.Concepts of Microoperations are given with suitable examples.Different kind of interrupts are illustrated for easy grasp of the subject matter.Each assembly language program is first explained with a flowchart and then written using mnemonics for clear understanding. Associative, Cache and Virtual memory organization form the backbone of computer architecture. All these are explained using illustrative diagrams.Set of questions with answers is added at the end of each chapter.Comprehensive glossary and index included for easy access to numerous terms needed for understanding the subject.Embedded system and its comparison with PC is added for ready reference.System programming is introduced for better understanding of computer architecture.