Culture clash
Fans cool your face and maybe even your temper, but that’s not all: They
transmit secret messages, are crucial dating props and deadly weapons.

Japan
En garde! In the Japanese martial art tessenjutsu, fans are used to parry knives or swords, and also to provoke attacks. Even the Samurai used to use the harmless-looking fan as a secret weapon, its metal ribs sharpened to a point. Potentially deadly, such fans could come in useful on occasions which required that swords be set aside.
Spain
Can you read me? Spanish fan gestures like “Follow me!” (1), “I love you” (2), “I love someone else” (3) were once used to convey secret messages. Some fan researchers claim that they were really just a 19th-century marketing trick, but fans really are great flirt aids, even without the knowledge of a complex secret code.