Grouping the regions of the electromagnetic spectrum by frequency

Electromagnetic Spectrum

A range of all types of electromagnetic radiation, characterised by various frequencies or wavelengths.

Frequency

The number of waves that pass a fixed place in a given amount of time, measured in Hertz (Hz).

Wavelength

The distance between corresponding points of two consecutive waves.

Radio waves

Have the lowest frequencies and longest wavelengths in the electromagnetic spectrum, ranging from 3 Hz to about 300 GHz. Used for television and radio transmission.

Microwaves

Follow radio waves in the spectrum, ranging from 300 GHz to 300 THz, and used for radar, satellite and mobile communication, and microwave ovens.

Infrared

Frequencies ranging between 300 GHz (0.3 THz) and 430 THz, applied in thermal imaging cameras, fibre-optic cables, and television remotes.

Visible light

Ranges from 430 THz to 790 THz, the part of the spectrum that can be detected by the human eye, giving us colours from red to violet.

Ultraviolet (UV)

Frequencies between 750 THz and 30 PHz, used for sterilisation, detecting forged bank notes, and assisting bees and butterflies in visual navigation.

X-rays

Fall between 30 PHz and 30 EHz in the spectrum, primarily used in medical imaging and treatment of cancers.

Gamma rays

Have the highest frequencies of more than 30 EHz, can be destructive due to high energy, and are used for sterilisation, treating cancers, and as a by-product in nuclear power plants.