The canto is a principal form of division in a long poem, especially the epic. The word comes from Italian, meaning "song" or singing.
Famous poems that employ the canto division are Luís de Camões's Os Lusíadas (10 cantos), Lord Byron's Don Juan, Valmiki's Ramayana (500 cantos), Dante's The Divine Comedy (100 cantos), and Ezra Pound's The Cantos (120 cantos).