"Armide" is an opera composed by Jean-Baptiste Lully with a libretto by Philippe Quinault. Premiering in 1686, it is based on the story of a sorceress named Armide who struggles between her love for a knight, Renaud, and her desire for revenge. The opera is notable for its rich orchestration and elaborate staging, characteristic of the French Baroque style. The work is divided into five acts and features a blend of drama, romance, and supernatural elements. "Armide" is celebrated for its beautiful arias and the emotional depth of its characters, making it a significant piece in the history of opera.