Tone poem is a single-movement orchestral work that depicts a story, scene, painting, or idea — also called a symphonic poem.
Franz Liszt invented the symphonic poem (or tone poem) in the 1840s and 1850s, composing thirteen single-movement orchestral works inspired by literature, painting, and philosophy — 'Les Préludes' (1854) is the most famous. The form gave 19th-century composers a way to write programme music outside the formal demands of the symphony. Bedřich Smetana's 'Vltava' (The Moldau, 1874) traces a river from source to sea. Richard Strauss raised the tone poem to its peak with works like 'Don Juan' (1888), 'Till Eulenspiegel' (1895), 'Also sprach Zarathustra' (1896, immortalised by Kubrick in '2001'), and 'Ein Heldenleben' (1898). Sibelius's 'Finlandia' (1899) became a national anthem in disguise. Debussy's 'Prélude à l'après-midi d'un faune' (1894) crossed into impressionism. The tone poem proved that pure orchestral music could narrate, depict, and argue without a single sung word.