Essentially, spectroscopy is the study of radiated energy and matter to determine their interaction, and it does not create results on its own. Spectrometry is the application of spectroscopy so that there are quantifiable results that can then be assessed. Mass spectrometry (MS) is an analytical technique that measures the mass-to-charge ratio of ions. These spectra are used to determine the elemental or isotopic signature of a sample, the masses of particles and of molecules, and to elucidate the chemical identity or structure of molecules and other chemical compounds. High resolving power can be obtained by mass spectrometry itself.