Electromagnetic waves span a wide range of wavelengths, known as the electromagnetic spectrum. The spectrum encompasses various types of waves, from those with very long wavelengths to those with very short wavelengths.
The electromagnetic waves with the shortest wavelengths are referred to as gamma rays. Gamma rays have extremely high frequencies and energies. They are produced by processes such as nuclear reactions, radioactive decay, and high-energy particle interactions. Gamma rays are often associated with phenomena such as nuclear explosions, certain types of radioactive decay, and astrophysical events like supernovae and black hole accretion disks.
In terms of the electromagnetic spectrum, gamma rays have wavelengths shorter than X-rays, ultraviolet (UV) rays, visible light, infrared (IR) rays, microwaves, and radio waves. They have the highest energy and frequency among all electromagnetic waves.