Music is an integral part of Mongolian culture. Among the unique contributions of Mongolia to the world's musical culture are the long songs, one of the greatest features of the Mongolian music, overtone singing and morin khuur, the horse-headed fiddle. The music of Mongolia is also rich with varieties related to the various ethnic groups of the country: Oirats, Hotogoid, Tuvans, Darhad, Buryats, Tsaatan, Dariganga, Uzemchins, Barga, Kazakhs and Khalha.