Braille
Braille is one of the most important codes in the world. It is used by blind people to read and write.
There are six dot positions, and the dots are raised up (so you can feel them) in special patterns.
Each pattern of dots is a "character" (a letter or number, and so on)
The Braille Alphabet
These are the dot patterns for the 26 letters of the alphabet:
Notice that k to t are like a to j, just with an extra dot in the lower left corner.
Also, if you took out w, then u to z is like a to e but with two extra dots ... the original code didn't include w!
Numbers
The patterns for the numbers are exactly the same as for the letters a to j.
So there's this special character to put in front of numbers:
Example: 3.1416
Without the "num" character it looks like "c.adaf"
Punctuation
Capital Letters
Capital Letters are shown by placing this special character before the letter:
Example: Hi Dad!
Example: Braille in Public Spaces
Many public buildings have Braille on signs to help visually impaired people be independent.
Practice
Our examples have all shown the Braille character with its matching letter or number, but that's not normally done.
Can you tell what this says?
Answer: Math is Fun
And how about this one?
Answer: A braille master!
How Many Combinations?
Each of the 6 dot positions can be either raised or flat (2 choices per dot).
2 × 2 × 2 × 2 × 2 × 2 = 26 = 64 combinations
That gives 63 characters plus an empty space (which acts as a space between words), plenty of room for letters, numbers, and punctuation.
Dots are Numbered
The dots are numbered like this:
| 1 • | • 4 |
| 2 • | • 5 |
| 3 • | • 6 |
These are dot positions, not the numbers themselves, which are shown here.