The circumgalactic medium (CGM) refers to the gas and dust that surrounds a galaxy, extending beyond its visible boundaries. This region plays a crucial role in the life cycle of galaxies, as it is the interface between the galaxy's interstellar medium and the intergalactic medium. The CGM is thought to contain a significant portion of a galaxy's baryonic mass and is believed to be a key component in regulating the evolution of galaxies by influencing their star formation and growth. Studying the CGM can provide insights into how galaxies acquire and lose gas, how they interact with their surroundings, and how they evolve over cosmic time. This research area is interdisciplinary, involving the fields of astrophysics, cosmology, and galactic dynamics.