With light, the faster the wave bobs up and down—the higher its frequency—the more energy it has. (Also, the higher its frequency, the smaller its wavelength: the distance between two wave crests.) Indeed, one of the most important thermodynamic laws—the so-called Stefan-Boltzmann equation—seems to tie the wiggles of molecules to the wiggles of light. It relates the temperature of an object to the total amount of light energy it radiates. This was the biggest victory for statistical mechanics and the wave theory of light.
