Four equations that organize almost the entirety of classical electricity and magnetism.

Maxwell’s equations are four fundamental equations that describe how electric and magnetic fields are created, changed, and linked together. They explain how charges produce electric fields, how currents and changing electric fields generate magnetism, and how changing magnetic fields induce electricity. Together, the equations reveal that electricity and magnetism are not separate forces but parts of a single electromagnetic field. One of their most striking consequences is that electromagnetic disturbances travel as waves at the speed of light, identifying light itself as electromagnetic radiation. They are used primarily in electrical engineering, communications, and electromagnetic physics.