Quasar host galaxies are galaxies that contain a quasar at their center. Quasars are extremely bright and powerful sources of radiation and energy that are powered by the accretion of material onto a supermassive black hole at the galaxy's center. Host galaxies play a key role in understanding the formation and evolution of quasars, as well as the co-evolution of galaxies and their central black holes. Studying quasar host galaxies can provide insights into the physical properties, environment, and evolution of these galaxies, as well as the role of the central black hole in shaping their properties. This research area encompasses a wide range of topics, including galaxy formation and evolution, black hole accretion, and the interplay between galaxies and their central black holes.