A braille cell is made up of six dots arranged in two columns of three dots.
In the early nineteenth century there were over 20 different types of embossed type. A French army captain, Charles Barbier de la Serre invented a system of 12 dot cells.
Originally this system was to be used by soldiers to communicate without having to talk, which could give away their position. This system, called 'sonography', used the 12 dot cells to represent sounds rather than letters or words. The French Army did not use the system because it was too complicated.
Louis Braille, who lost his sight at an early age, devised a system of dots in the 1820s that forms the basis of today's braille code. Braille developed de la Serre's idea but decided that the 12 dot cells and the phonetic basis of the system made its use too clumsy. Braille experimented until he found the ideal configuration of 6 dot cells based on the alphabet. As a teacher and musician, Braille went on to devise the braille codes for mathematics and music.
Following Braille's early death at the age of 43 in 1852, it seemed as if this system might fall into disuse. But in the same year, France officially recognised braille as the approved method of reading and writing for blind people.
