Scientists have known for approximately seven decades that nuclear fusion reactions are a potentially important source of energy. A fusion reaction is one in which two small nuclei, such as protons or deuterons, combine with each other to form one...

A tokamak is a machine producing a toroidal (doughnut-shaped) magnetic field for confining a plasma. It is one of several types of magnetic confinement devices and the leading candidate for producing fusion energy. The term Tokamak is a transliteration...