My question is what compositional techniques were used in the 20th century? I have looked everywhere including my book and cannot find compositional techniques defined. Can you give me the definition of compositional techniques and then maybe I can figure out what they are looking for? Thanks.

Answer 1

This might help:
http://en.wikipedia.org/wiki/20th_century_classical_music

I searched at http://www.google.com for 20th century music composition techniques and found this, but if it doesn't tell you what you need to know, please repeat the search and see if there's any other site in the search results that does. If not, keep altering the search terms to get different results.