Einstein took the next step by working out that all radiation is quantized.
Quantized means that it is transmited in small packets.
He argued that an oscillating charge can accept or lose energy in small values of (Delta)E
(Delta)E = h(Delta)f.
Where h is Planck's Constant
h = the Plank constant 6.63 x 10-34 J sDelta E is the change in Energy
f is the frequency of light measured in Hertz
This energy is lost as electromagnetic radiation.
Therefore this radiation must be emitted in small packets, each containing (Delta)E.
He then suggested that each energy of radiation will have its own frequency.
Therefore he no longer thought of radiation from an object as continuous.
said it consisted of a series of "packets" of energy.
This meant that radiation was being thought of as a "packet of energy" but also as a wave because it had a frequency.
These packets of energy became known as photons.