(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.
or samisen (三味線), also sangen (三絃) — both words mean
"three strings" — is a three-stringed traditional Japanese
musical instrument derived from the Chinese instrument
It is played with a plectrum called a bachi.