A "libretto" is the text or script of an opera, musical, or other vocal work. It includes the lyrics sung by the performers and often provides stage directions and descriptions of the scenes. The libretto serves as a guide for both the singers and the audience, helping to convey the story and emotions of the performance. In the world of theater, the libretto is crucial for understanding the narrative and character development. Famous composers like Wolfgang Amadeus Mozart and Giuseppe Verdi collaborated with librettists to create memorable operas, where the libretto plays a key role in the overall artistic expression.