Braille
Braille is the name of a system of writing with a series of small raised bumps used for the blind. The bumps are arranged in a cell 2 wide and 3 high for the main alphabetic characters.
A B C
o . o . o o . . o . . . . . . . . .
Here the circles are the raised areas.
History
Louis Braille was born sighted, but went blind due to injury and infection at the age of 3. Ironically, an awl was the tool that blinded him and was the same tool he used to create the Braille writing system. His father was a leather worker and Louis was eager to use the tools of his father, leading to the accident.
He invented the writing system in a high school for the blind and taught his class mates how to use the new alphabet. His class mates were great fans of the system and used it to write journals and notes to one another. After matriculation Braille was hired on as a teacher at the same school.
The leadership of the school fought against the system of writing at first. It even banned its use and burned the Braille journals when found.
Eventually the system was allowed by the school administration and spread quickly over much of the world before Braille's death at a young age. Braille was sickly as a man with tuberculosis. His condition was aggravated by his hard driving ways that left him little sleep.