Biochemistry is the study of chemical aspects of life. Biochemistry governs all living organisms and living processes. Because life processes are governed by organic molecules the discipline of biochemistry relies heavily on fundamental principles of organic chemistry and other basic sciences. Biochemists actually were organic chemists who specialized in the chemistry of compounds derived from living organisms. The text provides an historical overview of some of the key contributions of the early chemists, and of modern 20th century biochemists who have lead the discipline to where it is today. By controlling information flow through biochemical pathway and the chemical energy flow through metabolism, biochemical processes give rise to the incredible complexity of life. This book encompassing 18 chapters, the book is written in a clear and lucid manner and each topic organized into sub-topics. For clarity the book has been illustrated with simple well-labeled diagrams. In this edition begins with an overview of the general clinical aspects of biochemistry, apart from that it also included molecular and immunological diagnostics section in which I have covered recent techniques used in the molecular biology.