Biotechnology (bio = the use of biological processes, and technology = to solve problems or make useful products), in the recent years, has created unprecedented opportunities, not only for the manipulation of biological systems for the benefit of logical systems for the benefit of mankind but also for undertaking studies to understand the fundamental life processes. Consequently, it has become the world’s fastest growing and most rapidly changing technology. I feel pleasure in presenting fourth enlarged edition of the book. New information keeps on expanding and enriching every sphere of knowledge. The primary motivation for preparing this text was our own need for organising a document on the subject that presents the current scenario of advancements in fundamental concepts and the perspectives of application. Table of Contents.. Biotechnology: An Overview DNA, Gene, Genome, Protein Synthesis and DNA Chip Technology Applications of Genetic Engineering Enzymes in Genetic Engineering (Nucleic Acid Enzymology) Gene Cloning Vectors Techniques for Genetic Engineering Genetic Engineering Techniques Expression of Induced Genes Gene Silencing and Antisense Technology Scope, Achievements and Hazards of Genetically Modified Crops Eco-Social Impact of Genetically Modified Crops/Foods Plant Tissue Culture: Principles and Methodology Histological and Photographic Techniques for Plant Tissue Culture Protoplast Technology Micropropagation in Plants Somaclonal and Gametoclonal Variant Selection Gynogenesis and Crop Improvement Synseeds or Synthetic Seeds Animal Cell and Tissue Culture Immunology, Serology and Vaccines Animal Health Biotechnology Applications of Animal Biotechnology Transgenic Animal Technology Biotechnology in Fisheries Biotechnology and Transgenic Plants Biotechnology and Forestry Biotechnology of Biofertilizers Production Enzyme based Industrial Biotechnology Biotechnology: Production of Secondary Metabolites Biotechnology Biomass Energy Biotechnology Environmental Protection Biosensors, Biochips, Biofilms and Biosurfactants Biotechnology and Ethics Bioinformatics About the Author: Prof. (Dr.) Pravin Chandra Trivedi Ph.D., Post-Doct. (U.S.A.), F.L.S. (London), F.B.S., F.P.S.I., F.B.R.S., F.N.S.I., F.M.A., F.N.R.S.,F.I.A.T, F.E.S. Vice Chancellor, Jai Narain Vyas University, Jodhpur and MDS University, Ajmer; former Vice-Chancellor, Deen Dayal Upadhyaya Gorakhpur University, Gorakhpur (U.P.); Dr. Ram Manohar Lohia Avadh University, Faizabad (UP) and Maharaja Ganga Singh University, Bikaner (Rajasthan); former Professor, Department of Botany, University of Rajasthan, Jaipur, has a brilliant academic career standing First in all public examinations. Prof. Trivedi served as Head, Department of Botany and Co-ordinator; P.G. Course in Biotechnology (2003-06); Director, College Development Council (2001-04); and served on various administrative and academic positions in the University of Rajasthan, Jaipur. Prof. Trivedi has 40 years of teaching and research experience in the University of Rajasthan, Jaipur. He has published more than 350 research papers and review articles in Journals of repute and books. He has edited and written 174 Books (World record in the subject) and Guided 44 Ph.D. students. He has been the Principal Investigator of 21 major research projects funded by national organisations (U.G.C., C.S.I.R., I.C.A.R., D.S.T., D.B.T.). He is an elected fellow of nine reputed academic bodies. Dr. Trivedi visited several major research laboratories and delivered invited talks in many international conferences held in 15 countries (U.S.A., Canada, the U.K., Germany, The Netherlands, Italy, Japan, Denmark, Switzerland, Luxembourg, Malaysia, Singapore, Austria Belgium and France). For his outstanding contribution in Plant Sciences and education field he was decorated with a large number of awards and honors. To honor his contribution, Indian Botanical Society instituted a medal in his name “ Dr. P.C. Trivedi Medal for Editorial excellence” from 2019, which is being given every year for quality book (authored/ Edited) published by plant scientist. Prof. Trivedi has been a good teacher, researcher, author, editor, reviewer, adviser, promoter and populariser of science, traveler and, Photographer. Dr. Trivedi is truly portraying the sum total of these essential elements required in any serious teacher and researcher.