Improvisational comedy, often called improv, is a form of live theater where performers create scenes and dialogue on the spot, without a script. This spontaneous style relies on the actors' creativity, quick thinking, and collaboration, often incorporating audience suggestions to inspire their performances. Improv can take many forms, including short games, long-form narratives, or character-driven sketches. It emphasizes humor derived from unexpected situations and interactions, making each performance unique. Notable improv groups, such as The Second City and Upright Citizens Brigade, have popularized this art form, influencing television and film comedy.