A galactic halo is a vast, roughly spherical region surrounding a galaxy, containing dark matter, gas, and older stars. This area extends far beyond the main body of the galaxy and plays a crucial role in its formation and evolution. The halo helps to hold the galaxy together through gravitational forces. In addition to dark matter, the galactic halo may contain globular clusters, which are tightly packed groups of stars. The study of galactic halos provides insights into the history of galaxies, including their interactions and mergers with other galaxies, such as the Milky Way and its neighboring Andromeda Galaxy.