Braille uses a matrix of six dots to represent letters, numbers and other language features.
The rectangles are two dots wide by three dots high - some examples are shown below:
The black dots represent "bumps" which are raised so that they can be read using a finger.
We want to know how many possible patterns of bumps and flat spaces you can make.
The first pattern above has no bumps, and is not used in Braille, but it is still a valid pattern.