The expressions we have come across that describe the distribution of energy with regard to frequency, do not tell us what energy a particular vibrational mode has at any moment. We actually deal with small bands of frequencies which are composed of vibrations subject to random fluctuations of energy by quantum jumps. We have the concept that every thermal system tends to its state of maximum entropy. Over the whole span of frequencies, the energy tends to be distributed so that the system as a whole is subject to minimum change. This entropic tendency is within the three constraints: (i) the total energy is finite, (ii) there are a certain number of vibrations available, and (iii) energy changes are quantized. The quantized form of vibrational energy manages to get "transmitted" through the entropic "noise" to appear in the energy distribution curve. In the case of a gas, the quantized forms of energy are swamped by the noise except when we have states of very low or very high temperatures. It is very striking that the results obtained from a study of thermal radiation could find such applications as to the problem of the anomalies in the specific heats of solids. Eventually, of course, the original quantum hypotheses of Max Planck developed into the quantum and wave mechanics that today form one of the main branches of modern physics.