This lecture covers the physics of light, including electromagnetic waves, particles (photons), interference, photoelectric effect, and the wave-particle dualism. It delves into the properties of light in different regions of the spectrum, such as infrared, visible, ultraviolet, and X-rays. The lecture also explores the concepts of spectroscopy, polarization, ellipticity, circular dichroism, Raman scattering, Stokes, and Anti-Stokes phenomena.