Who is credited with the introduction of the concept of quantization that laid the groundwork for quantum mechanics?

The idea that energy comes in discrete packets was first introduced by Max Planck in 1900 when he explained black‑body radiation. He proposed that oscillators in a cavity could only emit or absorb energy in integer multiples of a basic unit, \(E = h\nu\), where \(h\) is Planck’s constant and \(\nu\) the frequency. This quantization step was the seed that later led to full quantum mechanics. For example, a vibrating string could only vibrate at frequencies that made its energy \(E = n\,h\nu\) with \(n\) an integer, showing that energy levels are not continuous. Planck’s insight opened the door to the entire quantum theory.