"Nanotechnology has created a great deal of pleasure world-wide and is being quoted as the key technology of the 21st century. Nanotechnology is the future of advanced development gaining importance rapidly as a most powerful technology dealing with everything today from clothes to foods there are every sector in its range we should promote it more for our future and for more expansions in our current life. In the chemistry nanotechnolgy involves the range of colloids, micelles, polymer molecules, and structures such as very large molecules or dense accumulation of the molecules. In physics of electrical engineering, the nanoscience is strongly related to quantum behavior or electrons behavior in structures with nano sizes. Also, in biology and biochemistry, there are interesting cellular components and molecular structures. The present book aims to reviews the previous work done and recent advancements in the field of nanotechnology. In this volume we have discussed the concept of Nanotechnology along with its history, applications, risks and development of nanotechnology. It is intended to present comprehensive information from a diversity of sources into a single volume to give some real examples, extending the concept that green nanotechnology is far from being a scientific conundrum, and instead a real answer to some of the actual problems the whole planet is dealing with. Emphasis is placed on material’s design, characterization, functionality, and preparation for implementation in systems and devices. The research in the area of carbon nanotubes, nano-polymers, nano-vectors, nanocomposites, nano-crystals, nanoparticles, nanofibers, nanoclays, nanotubes, nanofilters, nanohorn, nanowires, nanosprings, nanorods etc. have been reported. Various risks involved in using nanotechnology are also discussed because it is believed that the most disruptive future changes may occur as a result of molecular manufacturing, an advanced form of nanotechnology. The goal of this book is to provide an understanding for scientists and academicians all over the world to covering concepts, various new issues and developments in the area of nanotechnology."