Now that we have studied the wave model proposed by Maxwell, which states that light is an electromagnetic wave and whose quantum model would consist of a set of particles called photons, we are interested in knowing whether, after all, light is a wave or particle.
The truth is that there is no single answer to this question. It is correct to say that it depends on the phenomenon, since light sometimes behaves as a wave, sometimes as a particle. Therefore, we cannot say anything about what light actually is, but rather how it behaves in certain phenomena.
Some physical phenomena, such as interference and light diffraction, are explained by the wave model. Already the photoelectric effect, to be explained correctly, must make use of the quantum photon model. Thus, both models are important and complementary.
We call it wave-particle duality this double behavior of light.
It is noteworthy that both light and other electromagnetic radiation do not exhibit both behaviors simultaneously. This is the Complementarity Principle proposed by Niels Bohr.