Photon:A quantum of electromagnetic radiation, exhibiting properties of both a particle and a wave.
Quantum Mechanics:The branch of physics that deals with the behavior of matter and energy on the atomic and subatomic scale, where the wave-particle duality of particles is observed.
Double-Slit Experiment: A classic experiment that demonstrates the wave-particle duality of light, where light exhibits interference patterns like a wave but is also detected as discrete particles (photons).