Night writing visited the National Institute for the Blind in Paris, France, where he met Louis Braille. Braille identified the major failing of the code, which was that the human finger could not encompass the whole symbol without moving and so could not move rapidly from one symbol to another. His modification was to use a six-dot cell, the Braille system that revolutionized written communication for the visually impaired. Night writing Night writing, a.k.a. sonography, was a system of code that used symbols of twelve dots arranged as two columns of six dots embossed on a square of paperboard, and is now
Blind credential Blind credential A blind credential is a token asserting that someone qualifies under some criteria or has some status or right, without revealing "who" that person is — without including their name or address, for instance. It is used in maintaining medical privacy and increasingly for consumer privacy. It can be quite difficult to ascertain that someone is not using another's credential — identity theft — therefore a great deal of effort goes into the application of cryptography to authentication. Electronic money requires some blind credential system to assert that the money is valid, has not been already spent, and