Electromagnetic induction is the process by which a changing magnetic field generates an electric current in a conductor. This phenomenon occurs when a conductor, such as a wire, is exposed to a varying magnetic field, causing electrons in the conductor to move and create an electric current. This principle is the foundation for many technologies, including electric generators and transformers. In generators, mechanical energy is used to rotate a coil within a magnetic field, producing electricity. In transformers, electromagnetic induction allows for the transfer of electrical energy between circuits at different voltage levels.