Electromagnetic radiation propagates as waves that travel through space at the speed of light.

Electromagnetic radiation represents a form of energy transmitted through space in the form of waves. These waves are generated by the movement of electrically charged particles, such as electrons. When these charged particles move, they disturb the surrounding electric and magnetic fields, creating waves that propagate outward.

The waves of electromagnetic radiation are classified as transverse waves. In transverse waves, the oscillations occur perpendicular to the direction of travel. This is in contrast to longitudinal waves, such as sound waves, where the oscillations are aligned parallel to the direction of travel.

One of the remarkable properties of electromagnetic waves is their ability to travel through a vacuum; they do not require a medium for propagation. This is because the electric and magnetic fields are self-sustaining and can continue to propagate through space without the need for any physical medium.

The speed of electromagnetic radiation is constant and is equal to the speed of light in a vacuum, denoted by the symbol $c$. Consequently, all electromagnetic waves, regardless of their frequency or wavelength, travel at this same speed.

In summary, electromagnetic radiation propagates as waves traveling through space at the speed of light. These waves are inherently transverse and can traverse a vacuum without requiring any medium.