The Electromagnetic Spectrum is the full range of all possible Electromagnetic Radiation (EMF) frequencies. With electronic devices, we are most interested in the non-ionizing radiation spectrum.
Electromagnetic energy is radiation defined as Frequency (F) or Wavelength (W) (the inverse of frequency). The Frequency (F) spectrum starts close to zero (0) and can extend to infinity. The Wavelength (W) spectrum also starts around zero and extends to infinity, in reverse.
The following identifies frequency band designations, nominal frequency ranges, nominal wavelengths, and application uses.