Michael Faraday discovered electromagnetic induction in 1831: a varying magnetic field generates an electric current in a nearby conductor. The finding, documented in his Experimental Researches in Electricity (1831–1855), establishes the physical basis of the electric generator, the transformer, and all induction-based sensing technology. It is the physical foundation of all modern electric generators and motors — without induction, neither the power grid nor contemporary industrial civilization exists. Faraday's law was mathematically formalized by Maxwell in his equations of the electromagnetic field (1865), who explicitly cited Faraday as a fundamental conceptual source for his work.