Electromagnetic wave. What are electromagnetic waves? First, if we talk about electricity, we know that it can be static. And we can feel it when holding a balloon to the wall. Or makes your hair stand on end. And when we talk about magnetism, we know it can also be static like refrigerator magnet. But when they can change or move together, they make waves called electromagnetic waves. Electromagnetic waves are formed when an electric field couples with a magnetic field. The magnetic and electric fields of an electromagnetic wave are perpendicular to each other and to the direction of the wave.