Meet Russian astrophysicist Nikolai Kardashev, creator of the…

Meet Russian astrophysicist Nikolai Kardashev, creator of the Kardashev scale of civilization, a hypothetical measure of a civilization’s level of advancement as a function of energy consumption.

A Kardashev Type I Civilization utilizes all of the energy which reaches its planet from its parent star(s).

A Kardashev Type II Civilization utilizes all of the energy of its parent star(s), the most common theoretical mechanism of which is something along the lines of a Dyson Sphere.

A Kardashev Type III Civilization utilizes all of the energy of its parent galaxy.

Further iterations and variants of the scale have been proposed.