Let's first get an idea of how small a nanometer is.

One nanometer is a billionth of a meter, or a millionth of a millimeter. To put it in yet another way, one micrometer (or micron) is a thousandth of a millimeter, and one nanometer is a thousandth of a micron. In short, one nanometer is very, very small.

The nano world is governed by various rules that differ from those affecting our lives at the "human" level. Things that are not important at our level take on a huge significance at the nano level, and phenomena occur in the nano world that would be inconceivable at our level. The reason that nanotechnology is so revolutionary is that it seeks to control such nano-phenomena to realize completely novel capabilities and properties with effects in the world we see and experience everyday.