A GM, or Game Master, is a person who facilitates and oversees a tabletop role-playing game (RPG). They create the game world, develop the storyline, and control non-player characters (NPCs). The GM ensures that the game runs smoothly and fairly, guiding players through challenges and adventures. In addition to storytelling, the GM interprets the rules of the game and makes decisions to keep the gameplay engaging. They act as a referee, resolving disputes and adapting the narrative based on player choices. The role of the GM is crucial for creating an immersive and enjoyable experience for all participants.