Epic film is a style of filmmaking with large scale, sweeping scope, and spectacle. The usage of the term has shifted over time, sometimes designating a film genre and at other times simply synonymous with big budget filmmaking. Like epics in the classical literary sense it is often focused on a heroic character. An epic's ambitious nature helps to set it apart from other types of film such as the period piece or adventure film. Epic historical films would usually take a historical or a mythic event and add an extravagant setting and lavish costumes, accompanied by a expansive musical score with an ensemble cast, which would make them among the most expensive of films to produce. The most common subjects of epic films are royalty, and important figures from various periods in world history.