Quanta of light ( the smallest packet of energy
Planck’s work was revolutionary, but even Planck was not sure what it meant and tried for years to reconcile quantization with classical ideas. Moreover, Planck had quantized the oscillators emitting the radiation, not the radiation itself. He assumed that the radiation could be described by Maxwell’s equations. After all, these had been supported by the experiments of Hertz and others and their continuous fields seemed consistent with the continuous wave model of light established by Christiaan Huygens and borne out by experiments involving interference and diffraction (such as Thomas Young’s double-slit experiment).