Music is an art form whose medium is sound organized in time. Common elements of music are pitch (which governs melody and harmony), rhythm (and its associated concepts tempo, meter, and articulation), dynamics, and the sonic qualities of timbre and texture. The word derives from Greek μουσική (mousike), "(art) of the Muses".

The creation, performance, significance, and even the definition of music vary according to culture and social context. Music ranges from strictly organized compositions (and their recreation in performance), through improvisational music to aleatoric forms.

Music can be divided into genres and subgenres, although the dividing lines and relationships between music genres are often subtle, sometimes open to individual interpretation, and occasionally controversial. Within "the arts", music may be classified as a performing art, a fine art, and auditory art.

To people in many cultures, music is inextricably intertwined into their way of life. Greek philosophers and ancient Indians defined music as tones ordered horizontally as melodies and vertically as harmonies. Common sayings such as "the harmony of the spheres" and "it is music to my ears" point to the notion that music is often ordered and pleasant to listen to.

However, 20th-century composer John Cage thought that any sound can be music, saying, for example, "There is no noise, only sound." According to musicologist Jean-Jacques Nattiez, "the border between music and noise is always culturally defined which implies that, even within a single society, this border does not always pass through the same place; in short, there is rarely a consensus.… By all accounts there is no single and intercultural universal concept defining what music might be, except that it is 'sound through time'.

The development of music among humans must have taken place against the backdrop of natural sounds such as birdsong and the sounds other animals use to communicate.

Prehistoric music is the name which is given to all music produced in preliterate cultures.

Ancient music can only be imagined by scholars, based on findings from a range of paleolithic sites, such as bones in which lateral holes have been pierced: these are usually identified as flutes, blown at one end like the Japanese shakuhachi.

The earliest written records of musical expression are to be found in the Samaveda of India and in 4,000 year old cuneiform from Ur. Instruments, such as the seven-holed flute and various types of stringed instruments have been recovered from the Indus Valley Civilization archaeological sites.

India has one of the oldest musical traditions in the world references to Indian classical music (marga) can be found in the ancient scriptures of the Hindu tradition, the Vedas. The traditional music of China has a history stretching for around three thousand years.

Music was an important part of cultural and social life in Ancient Greece: mixed-gender choruses performed for entertainment, celebration and spiritual ceremonies; musicians and singers had a prominent role in ancient Greek theater In the 9th century, the Arab scholar al-Farabi wrote a book on music titled Kitab al-Musiqi al-Kabir ("Great Book of Music"). He played and invented a variety of musical instruments and devised the Arab tone system of pitch organisation, which is still used in Arabic music.