The rapid increase in primary energy use in the twentieth century is a hallmark of the modern world. But one form of energy stands out among all the rest: electricity. Energy use from all sources in the United States increased fourfold from 1920 to 2021. But the end use of electricity increased more than one hundred-fold over that same period, much of it generated from fossil fuels. The clear preference by society for electricity relative to other forms of energy is due to its unique physical attributes, which were translated into superior services in illumination and communication, and to unprecedented increases in the productivity of capital, labor, and raw materials in the manufacturing sector.