Qubits differ from classical bits, which are coded as only 0 or 1. A qubit can be a combination of both 0 and 1 simultaneously. One way to think of it is as a coin spinning between a 0 and a 1 axis.

President Donald Trump's order for the Defense Department to start testing nuclear weapons could lead to billions of dollars' ...

Questions have arisen after Russian President Vladimir Putin said his country tested two nuclear-capable weapons this week.