The speed of all electromagnetic radiation in a vacuum is 299,792,458 meters per second (m/s). This is also known as the speed of light and is often rounded to 3 x 10^8 m/s for simplicity.

Here's why this is important:

* All electromagnetic radiation travels at the same speed in a vacuum. This includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

* The speed of light is a fundamental constant in physics. It plays a key role in many physical theories, such as Einstein's theory of relativity.

* The speed of light can change slightly when it travels through different mediums. For example, light travels slower through water than through air.

Let me know if you have any other questions!