Abstract: The complete set of equations proposed by Jams Clerk Maxwell to describe the classical electromagnetic fields and their interaction with charged particles had combined electrics, magnetics and optics into a single unified theory of the electromagnetic fields. This theory possesses both Lorentz covariance and U(1) local gauge invariance, and has become a classical prototype for constructing the standard model of particle physics. Its role in the development of physical theories and experiments has been beyong measure.