This programme is about a revolution that could take the 21st Century by storm. A revolution in the way things are made, atom by atom and molecule by molecule. A revolution in making tiny robotic machines that are a hundred times smaller than bacteria. The buzzword is nanotechnology. What does it mean? A nanometer is a billionth of a metre. On the same scale a ping-pong ball is about a billionth the size of the earth. So nanotechnology is about the microscopically small. It is about knowing how to manipulate individual atoms and molecules to make everything from pharmaceuticals, materials and electronic devices to nanobots. This programme serves as a beginner's guide to a revolution whose outcome no one can predict.