Electric and magnetic phenomena have been known since antiquity. The twelfth-century invention of the magnetic compass is noted, and eighteenth-century research into static electricity is reviewed. Various properties and theories of electrical charge, electrostatic induction, and Coulomb’s inverse square law are described. Alessandro Volta’s invention of the electric cell in 1800 marked the start of modern electricity. Faraday’s concept of electric and magnetic fields revolutionized the field. The discoveries of Ohm’s law, Gauss’s laws of electrostatics and magnetostatics, and Kirchhoff’s electrical circuit laws are detailed, as are the development of the systems of direct current (DC) and alternating current (AC) power generation and its distribution to the city by Edison and Tesla. Oersted’s discovery of the link between electricity and magnetism marked the beginning of electromagnetism. The history of key contributions including the Biot-Savart law, Ampère’s law, Faraday’s laws of induction, Lenz’s law, and Maxwell’s equations of electromagnetic field is described. The chapter concludes with the classification and quantum theories of magnetic materials, as well as the discoveries of spin waves, integral and fractional quantum Hall effects, and magnetic moments.