The sensu or ōgi (folding fan) is an implement used to fan wind. It has been used in Japan by the nobility and monks as an accessory and a ceremonial item since the Heian period. Besides that, it also plays an important role in performing arts (such as Noh, Kyōgen, Rakugo and traditional Japanese dances) as well as in tea ceremony
The production of folding fans basically involves three main processes: the making of the ribs, the making of the fan surface, and the combining of the two parts. Each of these process is done through labour division by specialized craftsmen.