Modern classical music is music written in the 20th century and beyond. Although much of it draws heavily on earlier forms, modern composers also experimented with rejection of long-held ideas; notably, Arnold Schoenberg questioned the traditional notions of harmony with his twelve-tone system[?], and John Cage questioned the very definition of music with his use of chance and found sounds.
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Macrovision
iTunes
Windows media player[?]
DRM and document restriction technology
Opponents of DRM have noted that the proposed use of some DRM ...