The Symphony No. 9, Op. 125 (sometimes known simply as "the Choral"), is the final complete symphony of Ludwig van Beethoven. Completed in 1824, the symphony is one of the best-known works of the Western repertoire. Almost universally considered to be among Beethoven's greatest works, it was one of the first examples of a composer using voices in a symphony. The words, sung during the final movement by vocal soloists and a chorus, were taken from the Ode to Joy by Friedrich Schiller, with additions made by the composer. It stands as one of the most played symphonies in the world. In 2002, Beethoven's autograph score, held by the Berlin State Library, was added to the United Nations World Heritage List, becoming the first musical score to be so honoured.