ABSTRACT
The first fundamental fact is that electromagnetic waves propagate at a rate of approximately 300,000 kilometers (km) per second (s), or 186,000 miles per sin a vacuum. (This universal upper limit to the velocity that matter or information can achieve is usually abbreviated by "c?') The velocity of electromagnetic radiation in a vacuum is independent of frequency, so gamma waves, ultraviolet radiation, visible light, infrared (which is the range where practically all optical fiber traffic fits), and radio waves travel through space at the same rate.
