Complex sentence: Interactive storytelling (IS) is a form of digital entertainment in which users create or influence a dramatic storyline through actions, either by issuing commands to the story's protagonist, or acting as a general director of events in the narrative.
Split into simpler sentences: Interactive storytelling (IS) is a form of digital entertainment in which the storyline is not predetermined. The self-generated narrative is influenced by the actions of users, either by issuing commands to the story's protagonist, or acting as a general director of events in the narrative.