Last year, I stumbled across some of the cool history of American Sign Language, documenting how it evolved out of both formal and informal languages—systems Deaf children used to communicate at home, and the systems they were taught as Deaf schools drew diverse groups from a wide geographical range. For American Sign Language, this process happened in the 19th century. In other parts of the world, it's still ongoing. For instance, in Nicaragua, Deaf people who are in school now are learning a much more formalized language, with a much bigger vocabulary, than those who went to school in the 1980s.
Those international differences are fascinating to me, so I'm really pleased to find this post on the Sinosplice blog, discussing the Chinese system of finger spelling. The blogger there is a linguist, so there's a lot of neat perspective in the linked post and others on the linguistic mechanics of finger spelling and sign language in China.
Finger spelling is very different from a sign language. In a sign language, you'd have one hand movement or hand position that stands for the concept "bird." In finger spelling, you'd have several different movements/positions for each letter or sound of the word "bird." You probably picked up some American finger spelling from Sesame Street, it's likely to at least look somewhat familiar. But the really cool thing about this post, is that it contrasts that system with the finger spelling alphabets used in Russia, Japan, and several that have been used historically in China. That's the US system above. Below, the modern Chinese system that corresponds to the pinyin, a way of transcribing printed Chinese words into Roman letters.
Via Kerim Friedman