Yodel

Yodeling (or yodelling, jodeling) is a form of singing that involves singing an extended note which rapidly and repeatedly changes in pitch from the vocal or chest register (or "chest voice") to the falsetto/head register; making a high-low-high-low sound. This vocal technique is used in many cultures throughout the world.

In Alpine folk music, it was probably developed in the Swiss Alps and Austrian Alps as a method of communication between mountain peaks, later becoming part of the region's traditional music. In Persian classical music, singers frequently use tahrir, a yodeling technique that oscillates on neighbor tones. In Georgian traditional music, yodelling takes the form of krimanchuli technique, and is used as a top part in three/four part polyphony. In Central Africa, Pygmy singers use yodels within their elaborate polyphonic singing, and the Shona people of Zimbabwe sometimes yodel while playing the mbira[1]. Yodeling is often used in American bluegrass and country music. According to the Oxford English Dictionary the word yodel is derived from a German word jodeln (originally Bavarian) meaning "to utter the syllable jo."