  In modern physics courses the idea of photon has been teaching through from
the einsteinian formulation based on the photoelectric effect. Einstein's
photon concept allow the quantization of the electromagnetic field, but does
not dwell on the idea of photon as particle. The objective of this paper was to
demonstrate that the photon has its origin essentially in the special
relativity, the electromagnetic theory and in the symmetry between the
Lorentz's transformations associated flat monochromatic electromagnetic waves
and particles with zero rest mass. This approach allows to understand the
wave-particle duality of photon and allows to propose an alternative teaching
focused on this duality to develop the course of modern physics.
