The koto (Japanese: 箏) is a traditional Japanese stringed musical instrument derived from the Chinese zheng, and similar to the Mongolian yatga, the Korean gayageum, and the Vietnamese đàn tranh. The koto is the national instrument of Japan. Koto are about 180 centimetres (71 in) length, and made from kiri wood (Paulownia tomentosa). They have 13 strings that are usually strung over 13 movable bridges along the width of the instrument. There is also a 17-string koto variant. Players can adjust the string pitches by moving the white bridges before playing. To play the instrument, the strings are plucked using three finger picks, otherwise known as plectra, (on thumb, index finger, and middle finger).
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