古楽 (こがく) refers to "early music," a term used to describe music from the medieval, Renaissance, and Baroque periods, roughly from the 9th to the 18th centuries. This genre emphasizes the use of historical instruments and performance practices, aiming to recreate the sound and style of music as it was originally performed. Performers of 古楽 often use instruments like the lute, harpsichord, and viol, which differ significantly from modern instruments. The movement has gained popularity in recent years, with ensembles and soloists dedicated to exploring and reviving this rich musical heritage.