Kardashev Scale

The Kardashev scale is a method of measuring a civilization's level of technological advancement, based on the amount of usable energy a civilization has at its disposal. The scale has three designated categories called Type I, II, and III. A Type I civilization has available all the energy impinging on its home planet, Type II all the energy of its sun, and Type III of its galaxy. The scale is only hypothetical and in terms of an actual civilization, highly speculative; however, it puts energy consumption of an entire civilization in a cosmic perspective. It was first proposed in 1964 by the Soviet astronomer Nikolai Kardashev. Others have extended the scale to even more hypothetical Type IV beings who can control or use the entire universe, or Type V that control collections of universes. Metrics other than pure power usage have also been proposed, such as 'mastery' of a planet, system or galaxy rather than considering energy alone, or considering the amount of information controlled by a civilization rather than the amount of energy.