The term "star system" refers to a group or cluster of stars that are gravitationally bound together and move through space as a single unit. This can include multiple star systems such as binary, triple, or even more complex systems with multiple stars orbiting each other. The phrase is also used in another sense to describe the Hollywood film industry's system of categorizing actors based on their box office draw, popularity, and fame. In this context, it refers to the way that certain actors become "stars" and are given leading roles while lesser-known actors struggle to find work.