There were many new genres created and techniques implemented during the Modern era:
new tonalities: dodecaphonic, pandiatonic, bitonic, atonal, chromaticism, steps smaller than a minor second
stage productions incorporating dance
vocal chamber music using skilled soloists
new colors
wordless chorus-voice serving as instruments
percussive instruments, electronic instruments
focus on folk music
nationalism
new symbols for vibrato, falsetto, whispers, hisses, yelling, speech, extreme pitches, etc.
first to move away from Romantic trends
used new modes as means of expression
12 tone
atonality
electronics
eclectic music
avant-garde
graphic notation
more conservative choices
more conservative choices
conservative choices
not many composers
not much musical influence