The Second Viennese School is the group of composers that comprised Arnold Schönberg and his pupils and close associates in early 20th-century Vienna, where he lived and taught, sporadically, between 1903 and 1925. Their music was initially characterized by late-Romantic expanded tonality and later, following Schönberg's own evolution, a totally chromatic expressionism without a firm tonal centre, often referred to as atonality.

Arnold Schönberg (13 September 1874 – 13 July 1951) was an Austrian-born composer, music theorist, teacher, writer, and painter. He is widely considered one of the most influential composers of the 20th century. He was associated with the expressionist movement in German poetry and art, and leader of the Second Viennese School.

Alban Maria Johannes Berg (February 9, 1885 – December 24, 1935) was an Austrian composer whose style combined Romantic lyricism with the twelve-tone technique. Although he left a relatively small oeuvre, he is remembered as one of the most important composers of the 20th century for his expressive style.

Nikos Skalkottas (21 March 1904 – 19 September 1949) was a Greek composer of 20th-century classical music. He drew his influences from both the classical repertoire and the Greek tradition.

Wolfgang Amadeus Mozart (27 January 1756 – 5 December 1791) was a prolific and influential composer of the Classical period and a member of the First Viennese School. He is considered among the greatest classical composers of all time.

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