Music is an art form consisting of sound and silence. Elements of sound in music are pitch (which governs melody and harmony), rhythm (and its associated concepts tempo, meter, and articulation), dynamics, structure, and the sonic qualities of timbre and texture. 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. From : en.wikipedia.org/wiki/Music