"Musique Concrète (literally 'concrete music') is an experimental genre that uses any and all sound sources for its compositions. Original sounds are recorded and then modified through mixing and effect techniques, creating 'new' sounds that often deviate (sometimes substantially) from the original source material. Samples can be derived from traditional instruments, the human voice, or the acoustics of a natural environment, but also includes sounds created with synthesizers and computer modulation. Compositions in this idiom are also not restricted to the normal rules of melody, harmony, rhythm, or metre. By the early 1950s Musique Concrète was contrasted with pure 'Elektronische Musik' (which uses electronically produced sound near exclusively), but the distinction became so blurred that the term 'Electronic Music' now covers both genres. Musique Concrète has influenced many popular musicians, including The Beatles, Pink Floyd, Frank Zappa, and Lou Reed."