The developments in music after 1950 are not easily categorized from today's view, maybe some historical distance will be needed for this. Often these are micro-trends or styles, with only one or two protagonists.
Some of these different style directions are, for example: Neodadaism, electronic music, micropolyphony, „new simplicity“, „new complexity“, musique spectrale, algorithmic composition. Minimal music with its simple harmonies and rhythms is represented most prominently by Reich and Glass, the American Cage is considered the most important representative of aleatoric music.
Periodically “serious”, popular and even folk music inspire each other and turn away again. Electronic instruments and the new forms of digital production and manipulation have created radical new possibilities for the composers. Digital technologies permit the reproduction of sounds of most instruments as well as the creation of absolutely new sounds and offer before not practicable or never even anticipated experiments.
New publishing channels, as, e.g. the internet, offer possibilities for contemporary composers to present their works to the general public and to bring to performance.