Multi-star systems, also known as multiple star systems or multiple-star systems, are star systems in which two or more stars are gravitationally bound and orbit each other. These systems are relatively common in the universe, with some estimates suggesting that the majority of stars may be part of multiple star systems. Multi-star systems can have a variety of configurations, including binary systems (two stars orbiting each other), triple systems (three stars in orbit), or even more complex arrangements involving four or more stars. The dynamics of these systems can be quite complex, with the gravitational interactions between the stars leading to a variety of orbital patterns and behaviors. Studying multi-star systems can provide valuable insights into stellar evolution, as well as the dynamics of gravitational interactions within star systems. They can also offer clues about the formation and evolution of planetary systems, as the presence of multiple stars can influence the formation and stability of planets orbiting within the system. Overall, research on multi-star systems plays a significant role in advancing our understanding of the structure and behavior of stars and their interactions within complex stellar systems.