Type Wavelength Frequency
electric waves < 30 kHz
radio waves 10 km - 10 cm 30 kHz - 3 GHz
micro waves 10 cm - 100 μm 3 GHz - 3 THz
infrared radiation 100 μm - 700 nm
light 700 nm - 380 nm
ultraviolet radiation 380 nm - 10 nm
X-rays (Röntgen radiation) 10 nm - 100 pm
γ-rays (gamma radiation) 100 pm - 0.1 pm
cosmic radiation < 0.1 pm
Electromagnetism is a common denomination for a group of related forms of energy
that share the characteristic that no medium is required for their propagation. All
manifestations of electromagnetism exist in space in smaller of larger quantities. The
physical characteristics of the different types of electromagnetic radiation primarily
depend on their frequency or wavelength. The exact classification of the different
wavelength- and frequency bands, as well as the upper and lower limits of the
electromagnetic spectrum itself, is rather arbitrary. In many tables for instance,
electric waves and cosmic radiation are not mentioned as part of the electromagnetic
spectrum. All bands show some overlap and there is no widely accepted
standardisation. The table listed below is therefore an indication only. Notice the fact
that radiations with relatively long wavelengths are often characterised by their
frequency while radiations with relatively high frequencies are often characterised by
their wavelength.