Electromagnetic waves are characterized by a broad range of wavelengths and frequencies, each associated with a specific intensity (or amplitude) and quantity of energy. This wide range of wavelengths describes the electromagnetic spectrum.

An electromagnetic wave propagates (moves) in the direction of the vibrations of both the electric and magnetic oscillating field vectors. The two fields are perpendicular to eachother, and they carry energy from the radiation source to an undetermined final destination. Similar to mechanical waves, every electromagnetic wave oscillates in a periodic fashion with peaks and valleys, and displays a characteristic amplitude, wavelength, and frequency.

Figure: The electric and magnetic oscillating field vectors.