Nu shu, or women's writings, is a written Chinese language that is distinct from Chinese characters. It was exclusively used by women, who were otherwise illiterate, and was syllabic instead of pictographic. Moreover, it was sung rather than spoken when read aloud. Shared among women who swore each other to sisterhood, it appeared in books, on fans that doubled as letters, and in hidden embroidery. The topics dwell on the hardship of women's lives, the pain of forced arranged marriage, and the love of one's female friends.

Fascinating as the concept is, it's difficult to learn anything about even within China--it's mostly died out, and many writings were destroyed during the Cultural Revolution. There's a book on the topic, called We Two Know the Script; We Have Become Good Friends, and a film called "Nu Shu."

The film was produced in Canada and filmed in China. It's barely an hour long, and it wanders all over the place while telling the story of some of the few surviving nu shu women. However, it's very engrossing, and has a number of things to add to the story of nu shu. The filmmaker, Chinese-Canadian Yueqing Yang, points out that the suicide rate of women in these areas was lower than in other rural areas, perhaps because of this outlet. (Rural Chinese women have the highest suicide rate in the world.)

Anyway, it's all very intriguing if you're interested in linguistics, anthropology, women's studies, gender studies, or China. Book and film both highly recommended.