Forking Paths almost requires variation by having the user create each letter every time they need it.
The file for the typeface contains no actual letters, just a series of blocks in a three-by-three grid.The user generates these blocks using a computer’s numeric keypad. Each block corresponds to a number’s position in the keypad. Since, 7, for example, sits at the top left of the keypad’s grid, pressing 7 generates a block in the top left of the grid. Certain combinations of numbers produce blocks that span two or more of the grid’s squares. For example, typing 7 and 8 in order creates a bar that spans the top left and middle squares of the grid.
By utilizing these features, every user creates the font as they see fit.