


Music may be deliberately composed to be unperformable, or agglomerated electronically from many performances. In a free jazz context, there may be no structure whatsoever, with each performer acting at their discretion. In modal jazz the performers may take turns leading and responding, while sharing a changing set of notes. For instance, in Hindustani classical music, the performer plays spontaneously while following a partially defined structure and using characteristic motifs. In some musical contexts, a performance or composition may be to some extent improvised. There are solely instrumental pieces, solely vocal pieces, pieces that combine singing and instruments, pieces with no sound, randomly generated pieces, and even pieces merely specifying an environment with no further sonic organization. Pieces may be composed and performed using a vast range of instruments, including the human voice. Individual periods of music are separated into pieces, which can be categorized into numerous traditions, such as songs, tracks, symphonies, or so forth. It is sometimes more valuable to categorize music by era, scene, intent, or artistic inspiration. The mere existence or legitimacy of a genre may be a topic of controversy. The relationships and divisions between musical genres are loose and sometimes hotly contested, as in taxonomy.


The creation of music is commonly divided into musical composition, musical improvisation and musical performance. While scholars agree that music is defined by a few specific elements, there is no consensus on their precise definitions. Exact definitions of music vary considerably around the world, though it is an aspect of all human societies, a cultural universal. Music is generally defined as the art of arranging sound to create some combination of form, harmony, melody, rhythm or otherwise expressive content.
