(Translated by https://www.hiragana.jp/)
gagaku - Britannica Concise
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Traditional court and religious music of Japan.

It first appeared in Japan as an import from Korea in the 5th century AD and had become established at court by the 8th century. Though little notation from before the 12th century survives, a mostly later body of music continues to be performed at Shinto ceremonies. Gagaku employs transverse flute (ryuteki), double-reed pipe (hichiriki), mouth organ (sho), gong (shoko), drums, and stringed instruments including the biwa (see pipa) and koto. It may accompany dance (bugaku) or be played independently (kangen); it is further classified either as togaku, the so-called music of the left (which included Chinese and Indian materials), or as komagaku, the music of the right (including Korean examples). (The terms left and right were derived from the Confucian-based administration system of the capital during the Heian period.)

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bugaku mask
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