Computers are the most versatile machines ever invented, and the same piece of hardware can be used for thousands of different purposes. They can create virtual worlds with extraordinary realism, play chess better than almost any human, and even isolate a person’s position to within a few metres anywhere on the planet. What makes this possible is something that cannot be seen, felt or touched, but without it the digital revolution would never have happened. Professor Bishop investigates the software that brings a machine to life, and turns it into a phone, a music player, a game, or any number of other devices – including ones not even imagined by the creator of the hardware. So what is software, and how is it stored inside the computer? Is data the same thing as information? Why are some problems just too hard for any computer to solve, and how can this be used to a scientist’s advantage? To answer these questions, Professor Bishop explores how software has touched almost every aspect of life. He finds out how powerful new computers running sophisticated programs are able to do thousands of tasks at once, and why the simultaneous calculations made by a quantum computer may outnumber atoms in the universe. Finally, with the help of a live satellite link, the studio audience will put their burning questions about software to one of the pioneers of computing – co-founder of Microsoft and the world’s third richest man, Bill Gates.