Quantum physics is a fundamental theory in physics that describes nature at the atomic and subatomic particle level. Wave-particle duality, uncertainty principle, quantization of energy and momentum are central aspects of quantum physics. It has diverse applications in quantum optics, quantum computing, quantum chemistry, medical and research imaging, etc. The behavior of subatomic particles that make up matter, such as electrons, protons, neutrons, etc. is governed by quantum mechanics. It also plays a foundational role in string theory and computational chemistry. The quantum field theory that studies the strong nuclear force is under the scope of quantum chromodynamics. It describes the interactions between quarks and gluons. The weak nuclear force is unified with electromagnetic force in their quantized forms through the approach of electroweak theory. The ever-growing need of advanced technology is the reason that has fueled the research in the field of quantum physics in recent times. This book brings forth some of the most innovative concepts and elucidates the unexplored aspects of this field. Coherent flow of topics, student-friendly language and extensive use of examples make this book an invaluable source of knowledge.