Here's why:

* Speed of light: Electromagnetic waves travel at the speed of light in a vacuum, which is approximately 299,792,458 meters per second. This is the fastest speed anything can travel in the universe according to our current understanding of physics.

* Examples: Light, radio waves, X-rays, and gamma rays are all examples of electromagnetic waves.

While other waves, like sound waves or water waves, can travel quite fast, they are ultimately limited by the medium they travel through. Electromagnetic waves, on the other hand, don't need a medium and can travel through the vacuum of space.