Nanotechnology is that field of physical sciences which deals with the study of matter at nanometer scale. A nanometer is typically one billionth of a meter. For comparison, a single human hair is about 80,000nm wide, ared blood cell is approximately 7,000 nm wide and a water molecule is almost 0.3 nm across. Nanoscience deals with the study of matter and phenomenon at this scale while the term Nanotechnology deals with the applications of the events and the phenomenon happening at the nanoscale. In some senses, nanoscience and nanotechnologies are not new. Chemists have been making polymers, which are large molecules made up of nanoscale subunits, for many decades and nanotechnologies have been used to create the tiny features on computer chips for the past 20 years.

The breakthrough was the talk from great physicist Richard Feynmann which said "There is plenty of room at bottom". The entire magic revolves around the surface. This is so because as we lower the dimensions of a bulk object, we are gradually exposing its surface area. The second unique thing happening at the nanoscale is that the quantum effects begin to dominate the behaviour of matter at the nanoscale. Materials can be produced that are nanoscaled in one dimension(for example, very thin surface coatings), in two dimensions(for example nanowires and nanotubes) or in all three dimensions(for example, nanoparticles).This results in significant changes in the vital physiochemical properties of a substance ranging from physical, electrical, magnetic, optical and upto even electromagnetic. This is proved best by the different colours of gold at bulk and nanoscale. There are two main approaches, viz. Top-down and Bottom-Up. The former deals with making smaller objects from the bulky ones while the latter deals with just the opposite. Obviously, the principles involved are quite different. The techniques of lithography and nanoscale patterning have added further interest to the world of Nanotechnology. The most important implication of the Nanoscience is that laws of classical physics no more hold the validity. Rather, the defining science is Quantum Mechanics. This implies that energy is no more discrete at the nanoscale. The main reason behind the less study of nanoscale events is that we did not have finer tools which can make the nanoscale happenings visible and controllable.

The advent of techniques like Scanning Electron Microscopy, Transmission Electron Microscopy, Atomic Force Microscopy, Confocal Microscopy has added a new charm to the field of Nanotechnology. Micromachining is another aspect which requires to be accomplished to enhance the nanoscale functioning. Research into Nanotechnology attracts persons from diverse backgrounds ranging from Physics, Inorganic Chemistry, Applied Mechanics, Biotechnology and even Chemical Engineering. The application areas of this field are extremely versatile ranging from defence, composites, textiles, better and fast immunotesting and so on. Nanobiotechnology for example, has exploited the role of molecular motors and their versatility. Nanomedicine has explored the possibility of nano drug delivery for dealing with deadly blood- brain disorders and cancers like leukaemia. Nanotechnology has made diagnostics faster and more accurate. It has increased shelf life of foods, beverages, traditional textiles and provide a solution to a great number of imposing problems. Lab-on a chip has made possible the diagnosis of a number of different disorders simultaneously in no time. It has just revolutionized the day to day walks of human life from head to toe.

At the same time, there are so many ethical issues related to the rapid advances being made through this new field. We are just changing everything and this has led to a strong sense of concern by society. That's why the acceptance of the nanotechnological innovations are still in initial phase. No doubt, it has made life more risky and dependent on machines, still we have to focus on sustainable development so that this budding field can rejuvenate the life of every citizen and be potentially useful. This is so because Science can't do anything without the existence of nature.

About Author / Additional Info:
Parth Malik from India