|Nowhere to go
Computers have been getting more powerful. This is because transistors, the basic building blocks of computer chips, have been getting smaller. So we can cram more in.
But computers have a problem. Transistors are already nearly on an atomic scale and wires can't get any thinner than one atom wide. This means there is a physical limit to how small we can make transistors.
|At the moment the number of transistors on a computer chips doubles every 18 months.|