Music is an art form whose medium is sound and silence. Its common elements 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. It may also be divided among art music and folk music. There is also a strong connection between music and mathematics. Music may be played and heard live, may be part of a dramatic work or film, or may be recorded.
To many people in many cultures, music is an important part of their way of life. Ancient Greek and Indian philosophers 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." Musicologist Jean-Jacques Nattiez summarizes the relativist, post-modern viewpoint: "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."
Prehistoric music can only be theorized based on findings from paleolithic archaeology sites. Flutes are often discovered, carved from bones in which lateral holes have been pierced; these are thought to have been blown at one end like the Japanese shakuhachi. The Divje Babe flute, carved from a cave bear femur, is thought to be at least 40,000 years old. Instruments such as the seven-holed flute and various types of stringed instruments, such as the Ravanahatha, 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) are found in the Vedas, ancient scriptures of the Hindu tradition. The earliest and largest collection of prehistoric musical instruments was found in China and dates back to between 7000 and 6600 BC. The Hurrian song, found on clay tablets that date back to approximately 1400 BC, is the oldest surviving notated work of music.
The ancient Egyptians credited one of their gods, Thoth, with the invention of music, which Osiris in turn used as part of his effort to civilize the world. The earliest material and representational evidence of Egyptian musical instruments dates to the Predynastic period, but the evidence is more securely attested in the Old Kingdom when harps, flutes and double clarinets were played. Percussion instruments, lyres and lutes were added to orchestras by the Middle Kingdom. Cymbals frequently accompanied music and dance, much as they still do in Egypt today. Egyptian folk music, including the traditional Sufi dhikr rituals, are the closest contemporary music genre to ancient Egyptian music, having preserved many of its features, rhythms and instruments.