Prior to and after World War 2, the United States became a center of musical activity. Many composers from Europe moved to the US, some of them even became faculty members.
- Jazz - Jazz can be traced back to earlier African-American music styles. Jazz music is particularly notable for its improvisation, harmonic progressions and syncopated (modified) rhythms.
- Concert Music - Many composers combined jazz music elements with other music styles such as classical and blues. Music during this time also spoke of nationalistic fervor. Some of the composers whose works were greatly appreciated were George Gershwin (Rhapsody in Blue), Aaron Copland (Rodeo) and Dmitry Shostakovich (The Golden Age).
- Serialism - Based on Schoenberg's 12-tone system which was continued by his student Anton von Webern. Mostly evident in the music of the 1950s and 60s but appreciation was limited to university professors and their students. Serialism used a strict musical formula that was difficult to play. Composers who used this technique were Milton Babbitt and Pierre Boulez, to name a few.
- Chance Music - Also called aleatoric or indeterminancy. A technique popularized by John Cage wherein the composer gives the musician the freedom to interpret his music.
- Electronic Music - Composers experimented with technology and how it affects certain aspects of music such as melody and rhythm.
- New Romanticism - A movement that began in eastern Europe. It is the desire for music that was expressive, haunting and mysterious, much like the music of the past. Composers who used this technique were George Crumb (Ancient Voices of Children) and Gyorgy Ligeti (Lux Aeterna), among others.
- Minimalism - Music that was simple, featured patterns that were repeated and supported by a steady beat. The music of Steve Reich and Philip Glass were labeled as such.
- Edgard Varese - One of the composers who experimented with music and technology. He wrote a piece for an orchestra composed of solely percussion instruments. Also experimented in taped music and electronic instruments.
- Henry Cowell - American composer, one of the inventors of an electrical instrument called "rhythmicon." Wrote pieces wherein the musicians played the keys of a piano by striking it with their forearms or wrists and strumming or plucking the strings.
- John Cage - American composer of the 20th century known for his innovative, avant-garde ideas of creating and appreciating music. He devised the "prepared piano."