All electromagnetic waves travel at the same speed and in a vacuum. They have the same speed as light – (3 × 108 m/s). Like light, the speed of electromagnetic waves depend on the material they travel through, and they travel the fastest in a vacuum.
The electromagnetic spectrum is continuous, which also means that there are no missing frequencies in the range.
Gamma rays have the shortest wavelength ( and the highest frequency), and radio waves have the longest wavelength with the lowest frequency.
