The interdisciplinary field which focuses on the manipulation and manufacturing of materials and devices on atomic, molecular and supramolecular scale, is called nanotechnology. Nanomaterials are the materials which range between 1 to 100 nm. Molecular nanotechnology is the technology that is used for designing complex structures with the help of mechanosynthesis process. Bottom-up and top-down approaches are the two main approaches used in this field. Some top-down approaches include focused ion beams, solid-state techniques, etc. The bottom-up approaches include molecular-beam epitaxy, supramolecular approaches. Some of the theories where nanotechnology is applied are nanoelectronics, nanomedicine, nanopillars, biosensors, nanorods, drug delivery, etc. This book is a compilation of chapters that discuss the most vital concepts in the field of nanotechnology. It elucidates new techniques and their applications in a multidisciplinary approach. As this field is emerging at a rapid pace, the contents of this book will help the readers understand the modern concepts and applications of the subject.