The three-act structure is a narrative framework commonly used in storytelling, including films, plays, and novels. It divides a story into three distinct parts: the setup, the confrontation, and the resolution. In the first act, the main characters and their world are introduced, along with the central conflict that drives the story. In the second act, the characters face challenges and obstacles related to the conflict, leading to a climax where tensions peak. The third act resolves the conflict, providing closure to the story and its characters. This structure helps create a satisfying narrative arc that engages the audience.