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.
... laws proposed or already enacted in various jurisidictions (State, Federal, non-US). Most would include in all computer systems obligatory mechanisms controlling use in ways ...