20th-century music refers to music that was written between the years 1901 and 2000, inclusive. The 20th century was a period of widespread experimentation, and many composers wanted the freedom to explore new compositional approaches without the restrictions and expectations that accompany traditional genres. As a result, there is no recognizable unified sound to the music of this period, and it is, in general, much more stylistically divergent than the preceding eras of Western art music. Some of the key features of 20th-century music include:

• Modernism: This is a movement that began in the early 20th century and sought to break with traditional tonality, resulting in diverse styles, techniques, and expression.

• Impressionism: This movement was developed in France and characterized by its use of color, atmosphere, and suggestion rather than explicit statement.

• Expressionism: This movement was characterized by its use of dissonance, atonality, and intense emotional expression.

• Neoclassicism: This movement sought to revive the forms and styles of earlier periods, such as the Baroque and Classical eras, while incorporating modern techniques.

• Electronic music: This genre emerged in the mid-20th century and involves the use of electronic instruments and technology to create and manipulate sound.

In addition to these movements, other genres and styles emerged during the 20th century, including minimalism, aleatoric music, microtonal music, and experimental music. The 20th century was also the first century of recorded music, which allowed for new forms of musical expression and dissemination.