A bamboo flute is a wind instrument made from a bamboo stem; there are many types in use worldwide, especially in folk music, as can be seen on this list of bamboo flutes. The oldest types of bamboo flutes are played as a transverse flute, which means that the player completely controls the tone production with his lips. Some of these instruments are literally played transversely, such as the North Indian bansuri; others are played half-transversely, such as the kaval from the Balkans or the ney from Asia Minor. Still others use a sharply ground edge and are played straight" (thus belonging to the family of straight flutes), such as the shakuhachi from Japan, the xiao from China, or the quena from South America, which has an extra notched slit to facilitate tone formation and is therefore considered to belong to the family of "notched flutes. The way of playing is sometimes also comparable to that of the recorder in more modern instruments: the tone is largely formed automatically in the instrument by the construction with the aid of a block. Hence the name recorder. The tone of a bamboo flute is always relatively soft, due to the softness and light weight of the material.