Molecular biology deals with the molecular basis of biological activity in and between cells, including molecular synthesis, modification, mechanisms, and interactions. The study of chemical and physical structure of biological macromolecules is known as molecular biology. In other words, molecular biology is an interdisciplinary approach to understanding biological functions and regulation at the level of molecules such as nucleic acids, proteins, and carbohydrates. The book “Molecular Biology: Principles and Techniques” is the classic in-depth text reference for undergraduate students. This book is written by extracting fundamental concepts and their accurate meaning from large growing fields. The book is concerned with molecular biology studies, macromolecules and the macromolecular mechanisms found in living things, such as the molecular nature of the gene and its mechanisms of gene replication, regulation, mutation, post transcriptional modifications and expression. In this book, we tried to explain the basic concepts of genetic material in a conversational language. It is written in a reader friendly way through which students and non-expert reader can understand it easily. To further make the things easy well-labelled diagrams have been provided. This book focuses on the structure, functions and internal control within individual cell at molecular levels. The contents of the book also reflect the major techniques used and their application to the molecular analysis of biological processes. These methods have tremendous value not only in the investigation of basic scientific questions, but also in application to a wide variety of problems affecting the overall human condition. We hope this book will fulfill requirements of reader. Contents.. Preface About the Author(s) History and Major Landmarks in the Development of Biotechnology Introduction to Gene and Genome Proteins and Proteome Industrial Fermentation Plant Tissue Culture Animal Cell Culture Genetic Engineering: Introduction and History Genetically Modified Organism DNA Fingerprinting Applications of Biotechnology Biotechnology Research in India Biotechnology in Context of Developing Countries Safety Guidelines and Risk Assessment in Biotechnology Ethics of Biotechnology Intellectual Property Rights Introduction to Nanotechnology Glossary About the Author: Dr. Mukesh R. Jangra is Assistant Professor in the Department of Biotechnology, Government PG College, Hisar. She has teaching and research experience of more than 7 years. Dr. Jangra earned her Ph.D. in the field of Microbial Biotechnology from the Department of Molecular Biology, Biotechnology & Bioinformatics, CCS Haryana Agricultural University, Hisar. Her research interests include Microbial Biotechnology and Bioinformatics. She has published more than 25 research articles in national and international journals. She has attended more than 20 national and international conferences/symposiums/seminars. She has presented five research papers at international conferences in different places. She has already published a practical manual for undergraduate students of biotechnology.