What's the theory of light stated by Albert Einstein

This theory states:

• Light energy is quantized, meaning it exists in individual "chunks" or particles called photons.
• The energy of a photon is directly proportional to its frequency (E = hf, where h is Planck's constant and f is frequency).
• When light interacts with matter (like in the photoelectric effect), it behaves as if these individual photons are colliding with electrons, transferring their energy.

This concept of light having both wave-like and particle-like properties is known as wave-particle duality.