Quantum physics is weird. Things can be in two places at once or spinning in two different directions at the same time.
We can normally ignore this absurdity since it only happens at the microscopic scale. However, soon machines that exploit these bizarre features could revolutionise computing.
Conventional computers store and process information as bits. A bit can be a 1 or a 0. A modern computer chip has millions (even billions) of electronic switches that can either be on to represent 1 or off to represent 0. The progress in computing over the past 70 years has been to shrink and speed up these switches.

The Colossus was the first electronic computer – these are valves from a recreation of the 1944 version
A quantum computer works very differently. Because it uses as its bits tiny particles , either atoms or subatomic particles, these are subject to the laws of quantum physics.
That means they can be in two states at the same time, so a quantum bit (or qbit) can be a 1 or a 0 or a 1 and a 0 at the same time. I will say that again. A qbit can be both a 1 and a zero at the same time.
So why might this revolutionise computing?
For all their amazing performance, conventional computers have their limitations. There are some problems so difficult that all the computers that have ever been built could work together and still not find the answer before the sun explodes.
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