The Nobel Prize in Physics was awarded to three scientists on Tuesday for discovering that a bizarre barrier-defying phenomenon in the quantum realm could be observed on an electrical circuit in our classical world.

The discovery, which involved an effect called quantum tunneling, laid the foundations for technology now being used by Google and IBM aiming to build the quantum computers of the future.

Here is what you need to know about the Nobel-winning work by John Clarke of the UK, Frenchman Michel Devoret and American John Martinis.