Definition of Braille system
Braille system: A system of raised-dot writing devised by Louis Braille (1809-1852) for the blind in which each letter is represented as a raised pattern that can be read by touching with the fingers.
The System: Each braille character or "cell" is made up of 6 dot positions that are arranged in a rectangle comprising 2 columns of 3 dots each. A dot may be raised at any of the 6 positions. Counting a space in which there is no dot raised, there are 2 to the 6th power (2x2x2x2x2x2 = 64) possible combinations. A specific combination is described by naming the positions where dots are raised. The positions are numbered 1 through 3 from top to bottom on the left, and 4 through 6 from top to bottom on the right.
For example, a combination of dots 1-3-4 describes a cell with three dots raised, those dots being at the top and bottom in the left column and on top of the right column. The 1-3-4 combination denotes the letter "m" in French and in all other languages (including English) that use the Roman alphabet. The same 1-3-4 combination designates the letter "mu" in Greek and "mim" in Arabic (both of which have an "m" sound).
The basis of the braille codes for all of the world's languages is the assignment of most of the dot patterns to letters of the alphabet, punctuation marks and other symbols. This is done with a certain consistency, quite often with reference to Louis Braille's original assignments (to the extent that is possible, given the great diversity of alphabets, accent marks, vocalization marks, etc).
Because the 64 distinct characters are never enough to cover all possible print signs and their variants, it is necessary to use multi-character sequences for some purposes. Often this is accomplished by using certain characters as "prefixes" or "indicators" that affect the meaning of subsequent cells.
For example, in English a dot 6 before a letter indicates that the letter is a capital, whereas otherwise it is understood to be lower case. For another example, dots 3-4-5-6, called the "numeric indicator", causes certain following letters (a through j) to be reinterpreted as digits.
Other Braille Codes: Separate braille codes can be used for notation systems such as music, mathematics and computer programming, and even for pursuits such as chess. The basis of such codes remains an association between the 64 possible braille characters and the symbols and other notational elements of interest.
There is current research, under the auspices of the International Council on English Braille (ICEB), as to whether some of these separate codes, notably for mathematics and the sciences, should be combined along with the literary code into a single Unified Braille Code (UBC) for English.
Louis Braille: Louis Braille was born with normal sight. At age 3, while playing in his father's harnessmaking shop, he injured an eye with a sharp tool, an awl. The eye became infected and the infection affected his other eye, leaving him entirely blind. After succeeding brilliantly in the local school, he was sent at age 10 to the Royal Institution for Blind Youth in Paris.
A French army officer named Charles Barbier de la Serre invented the basic technique of using raised dots for tactile writing and reading, in order to allow soldiers to compose and read messages on the dark of the night. Barbier adapted his system and presented it to the Royal Institution for Blind Youth, hoping that it would be officially adopted there. He called the system Sonography, because it represented words according to sound rather than spelling.
Louis Braille analyzed Barbier's system and discovered the potential of the basic idea and the shortcomings in some of Barbier's specific provisions, such as a clumsy 12-dot cell and the phonetic basis. Within three years, by age 15, Braille had developed the system that we know today as braille based on a 6-dot cell and on normal spelling. He also went on to lay the foundations of the braille representation of music. Over 150 years after Louis Braille worked out his basic 6-dot system, its specific benefits remain unmatched by any later technology -- though some, computers being a prime example, both complement and contribute to braille.
Last Editorial Review: 6/14/2012
Back to MedTerms online medical dictionary A-Z List
Need help identifying pills and medications?