The difference between a two-digit number and the number obtained by interchanging the positions of its digits is $36$. What is the difference between the two digits of that number?

Let the two-digit number be represented as $10x+y$, where $x$ is the tens digit and $y$ is the units digit.
When the digits are interchanged, the new number is $10y+x$.

According to the question, the absolute difference between the original number and the reversed number is $36$:

$$|(10x+y)-(10y+x)|=36$$

$$|9x-9y|=36$$

$$9|x-y|=36$$

Dividing both sides by $9$:

$$|x-y|=\frac{36}{9}=4$$

Thus, the absolute difference between the two digits of the number is $4$.