Ultraviolet radiation, X-rays and gamma rays all have wavelengths that are shorter than visible light. The ultraviolet spectrum ranges from 400 to 10 billionths of a meter, X-rays from about 10 billionths to 10 trillionths of a meter, and gamma rays less than 10 trillionths of a meter.
Visible light is just a small part of the electromagnetic spectrum, which ranges from low frequency radio waves to high frequency gamma rays. The visible spectrum starts just above the infrared region and ends just below the ultraviolet region. Infrared is detected as heat, or thermal energy.
Ultraviolet radiation is one of the primary causes of sunburns. The shorter wavelengths penetrate clouds that typically block visible spectrum light.