Quark mixing is a phenomenon in particle physics where different types of quarks can transform into one another. Quarks are fundamental particles that combine to form protons and neutrons, which make up atomic nuclei. There are six types of quarks, known as flavors: up, down, charm, strange, top, and bottom. Mixing occurs due to the weak force, one of the four fundamental forces, which allows quarks to change their flavor. This mixing is described by the Cabibbo-Kobayashi-Maskawa (CKM) matrix, a mathematical framework that quantifies the probabilities of these transformations. Quark mixing plays a crucial role in understanding processes like beta decay, where a neutron decays into a proton, emitting an electron and an antineutrino. It also helps explain the observed differences in particle behavior and the generation of mass in the Standard Model of particle physics.