Nüshu (Women's Script)

Secret script used exclusively by women in Hunan, China — the world's only writing system transmitted by a specific gender (female). Hidden from men for centuries, it was used for letters to friends before marriage (the "Third Day Books") and bridal gift booklets. The last native speaker, Yang Huanyi, died in 2004. The Chinese government and academics are now conducting restoration and preservation work; it has been designated as Chinese Intangible Cultural Heritage.