The basic braille alphabet, braille numbers, braille punctuation and special symbols characters are constructed from six dots. These braille dots are positioned like the figure six on a die, in a grid of two parallel vertical lines of three dots each. From the six dots that make up the basic grid, 64 different configurations can be created.
There are some variations of the braille alphabet around the world. The punctuation, abbreviated characters and accented characters vary from country to country.
Here is the standartised alphabet:
Also, when indicating numbers the number sign should be placed before braille numbers to differentiate them from the letter symbols A to J. And also, A letter sign, or grade 1 indicator (⠰) is required to be inserted between numbers and letters when numbers are immediately followed by letters. See in these examples:
Also, braille has more punctuation:
Also, each braille letter could be represented as a number sequence based on this grid: