1. Braille

2. Learning objective To look at how and why Braille is created by breaking it down into simple steps. First the background… Braille is a way that blind people can read and write. It was invented in 1821 by Louis Braille, a blind Frenchman. Each Braille character, is made from six dot positions, arranged in a rectangle containing two columns of three dots each. The dots are raised at any of the six positions so they can be felt by the fingers.

3. Braille The 3 by 2 configuration Some dots are raised, why is this?

4. Braille How can we work out how many possible symbols there are? Is there an easy way to do it?

5. Braille How many possibilities are there with only one dot?

6. Braille How many possibilities are there with only one dot? Two

7. Braille How many possibilities are there with two dots?

8. Braille How many possibilities are there with two dots? Four

9. Braille How many possibilities are there with three dots?

10. Braille How many possibilities are there with three dots? Eight

11. Braille How many possibilities are there with four dots? Does it matter if it is placed in a column or a square?

12. Braille How many possibilities are there with four dots? Sixteen

13. Braille How many possibilities are there with five dots?

14. Braille How many possibilities are there with six dots?

15. Braille Why do you think the system with six dots was chosen?

16. Braille Why do you think the system with six dots was chosen? Napoleon wanted a code that soldiers could use to communicate silently and without light at night. The original system of 12 raised dots was too difficult for soldiers, so was rejected. So in 1821 Louis Braille worked out the problem, the finger could not feel the whole symbol without moving, he simplified it to six symbols which could easily be felt. As well as the letters, numbers, punctuation AND EVEN SYMBOLS were added, so the system with six raised dots with up to 64 configurations was used.