Eight episodes for children aged 6 to 8, hosted by Ben, an eight-year-old boy who works everything out alongside the child. The course runs on a shelf of eight steps, and the height of a step is not the size of the machine: it is WHEN it appeared. Every episode lights one step and opens a two-panel picture, the machine on the right and the world before it on the left, because no machine looks impressive on its own, and a light bulb only looks impressive next to a candle. It starts with the wheel, whose hard part was never the wheel but the axle, and with the printing press, made almost entirely of things that already existed. Then the steam engine, which solved WHERE power comes from and not speed; the bulb, which changed the clock rather than the light; the telephone, which stopped distance being measured in days and started it being measured in seconds; the aeroplane, whose first flight lasted twelve seconds; the fridge, which does not make cold but carries heat out of the door; and the computer, whose name was a job before it was a machine. It closes with the whole shelf lit and one idea: not one of these machines was made on its own.