Nanotechnology refers to the manipulation of atoms at the nanoscale level that has numerous worthwhile applications in the real world. Unique physical and chemical properties of nanomaterials can be exploited for high performing applications that benefit the society. Nanotechnology has the potential to penetrate the grassroots of the society, hence everyone should know and aware of this technology especially the students. Owing to the important of nanotechnology, this book 'Essentials of Nanoscience and Nanotechnology' has been prepared. This book contains nineteen chapters and covers both basics of nanoscience and nanotechnology and the applications of nanomaterials in varied disciplines. In the basics of nanoscience and nanotechnology part, this book briefs about the different properties of nanomaterials, various synthesis methods, and its characterization using important analytical instruments. Whereas in the application aspect, this book covers different disciplines, such as Agriculture, Food industry, Energy and Environmental Management, Medical science, Toxicology, and Biotechnology. This book has been written in a very simple format enabling easy understanding by the readers and students who have aspiration to know nanotechnology. All the chapters are framed, based on the ICAR's prescribed B.Sc. Agriculture Undergraduate syllabus, hence this book will be more useful for both Undergraduate students and general readers.