The symphony is one of the central forms of Classical music and one that has something new to say to each generation. Typically, a symphony is a multi-movement, multi-character work for orchestra, with origins in the sinfonias that served as curtain-raisers for operas in the early 17th century. In the Classical era, Haydn perfected the form, which would bring forth masterpieces from Mozart, Beethoven, Brahms, Mahler, Sibelius, Shostakovich, Ives, and so many others. As it developed, symphonies began to encompass more than abstract musical ideas, embracing programmatic narratives, nationalistic characteristics, and modern compositional techniques such as serialism. Even in the 21st century, when the costs -- financial and otherwise -- of performing such large-scale works can seem prohibitive, composers like Einojuhani Rautavaara, Philip Glass, and Tan Dun are still compelled to write them.