Schoenberg, Arnold  (1874–1951) an Austrian 
composer who went to the US in 1933. He invented the ‘twelve-tone system’ of writing modern music, in which music is written around a set of twelve notes of a 
chromatic scale. His system has influenced many modern composers. His works include
 Transfigured Night,
 Pierrot Lunaire, and an 
opera that he did not finish
 Moses and Aaron. 
 [TahlilGaran] Dictionary of Contemporary English ▲