Electromagnetic wave

A transverse wave composed of an oscillating electrical field and a magnetic field that oscillates perpendicular to the electric field.

Electromagnetic waves was predicted by the classical laws of electricity and magnetism, known as Maxwell's equations:

$\nabla \cdot \mathbf {E} =0\qquad \qquad \qquad \ \ (1)$

$\nabla \times \mathbf {E} =-{\frac {\partial }{\partial t}}\mathbf {B} \qquad \qquad (2)$

$\nabla \cdot \mathbf {B} =0\qquad \qquad \qquad \ \ (3)$

$\nabla \times \mathbf {B} =\mu _{0}\epsilon _{0}{\frac {\partial }{\partial t}}\mathbf {E} \qquad \ \ \ (4)$

where

$\nabla$ is a vector differential operator

Maxwell's equations is an example of a system of partial differential equations.