advanced instrument techniques, a multiplicity of musical genre in any given work, and multicultural structures and instrumentation as the film industry, and therefore the music composition industry, became more globalized. It exploded in the 1990s in America with the release of many different blockbuster films and a high demand for fully orchestrated soundtracks, but is now often replaced with soundtracks that are entirely synthesized or utilize covers songs of famous popular songs or are even composed by popular performers, such as in the soundtrack for the 1997 film Titanic (Titanic: Music from the Motion Picture) and the use of many popular songs for specific historical references in the soundtrack for the movie Forrest Gump (Forrest Gump (soundtrack)). Because of the growing common practice of using popular songs combined with a more classical soundtrack, it became a standard to release two soundtracks with one made of up the popular genre selected songs, and the original score or film score as mentioned previously. Significant American composers of film music include Wendy Carlos, Danny Elfman, Michael Giacchino, Jerry Goldsmith, Bernard Herrmann, James Horner, James Newton Howard, Erich Wolfgang Korngold, Randy Newman, Alan Silvestri, and John Williams. Classical and popular (non-classical) genre fusion compositions also developed in the United States, starting circa 1950s, with entertainers such as Liberace and composers such as Walter Murphy bringing classical music to different genre with their arrangements, such as in Walter Murphy's disco-classical fusion piece "A Fifth of Beethoven". Many disco versions of famous classical works were arranged in the 1970s, such as works by Beethoven, Mozart, Schubert, Wagner, Mussorgsky, J.S. Bach, and George Gershwin. Popular classical works are also referenced and covered frequently in the United States, also starting circa 1940s-50s, in cartoons, famously in Rhapsody Rabbit and The Cat Concerto, both using Franz Liszt's famous solo piano concert piece: Hungarian Rhapsody No. 2. 21st century See also Timeline of music in the United States References