This course explores the fundamental concepts of quantum optics with a focus on the behavior of single photons and is taught by Professor Alain Aspect. Throughout the course, learners are introduced to the quantum nature of light, the properties of single photons, photon measurement and detection, quantum interference, and several important experiments in quantum optics. It is suitable for those with a basic background in quantum physics and optics who want to develop a deeper understanding of light at the single-photon level.