The Faraday disk was the first electric generator. The horseshoe-shaped magnet created a magnetic field through the disk. When the disk was turned, this induced an electric current radially outward from the center toward the rim. The current flowed out through the sliding spring contact, through the external circuit, and back into the center of the disk through the axle.
Generators are devices that create or convert one type of energy into another. For instance, an electric generator transforms mechanical energy into electric power for use in an external circuit.
