Nanotechnology is the manipulation or self-assembly of individual atoms, molecules, or, molecular clusters into structures to create materials and devices with new or vastly different properties. Nanotechnology can work from the top down (which means reducing the size of the smallest structures to the nanoscale) or bottom up (which involves manipulating individual atoms and molecules into nanostructures) .The definition of nanotechnology is based on the prefix "nano" which is from the Greek word meaning "dwarf". In more technical terms, the word "nano" means 10-9, or one billionth of something.