The basic idea (…) is to replace the lack of sight with the sense of touch (…)
Valentin Haüy, 1784
Symbols and script are fundamental elements in our society for recording and passing on information. The saying “to have something in black-in-white” best describes in what form people with an intact sense of vision perceive script – optically, as “black” characters on a “white” background. While a seeing person perceives written or printed characters with his or her eyes, the blind or visually-impaired require another sense to do this. They conceive of the world not only with their marked sense of hearing, but also to a great extent using their sense of touch. This requires a special form of tactile writing – Braille, whereby a fundamental difference is made between raised dot type and recessed relief type.
While recessed relief types, such as Moon type display letters in their normal form or simplified as geometric figures, raised dot types translate letters, numbers and other characters – even musical notes – using a code into specific, tactile patterns of dots. Today, when people talk about writing for the blind and visually-impaired, they are mostly referring to Braille. This raised dot system, named after its inventor, the Frenchman Louis Braille, is based on a pattern of six dots with 64 possible combinations. Braille is the world’s most famous writing for the blind today and it has found its way into our everyday life in many places, for example, showing the way on handrails or on the packaging of medicines. However, transcribing literature into Braille is very complex and expensive and books in Braille are often extensive. The development of new hardware and software such as refreshable braille display, screen readers, Braille printers, or special apps also make it possible for the blind or the visually-impaired to use computer-based sources of information, like the World Wide Web, for example, in the age of increasing digitalisation.