The materials that the nano-world is concerned with are on the scale of atoms and molecules, and there are great differences between the way ordinary-sized materials and nano-sized materials behave.

Take iron, for example. In the everyday world, iron is iron, no matter what amount is involved. However nano-sized iron, made up of several dozen atoms not only looks different, but its physical properties are also different, maintaining a much stronger magnetic force.

Nano-sized iron cannot be used in the same way as everyday iron, but the special properties that its tiny size imparts can be used in completely new applications.