Trying to rub the dust from my math knowledge, I am trying to understand, or perhaps recall, the Modular Arithmetic and Modulo Operation but I kinda can't get what the differences are between these two is ? 
From Wikipedia : 

> 
> This section is about the (mod n) notation. For the binary mod
>  operation, see modulo operation. 
> 
> 
> 

[The link here](https://en.wikipedia.org/wiki/Modular_arithmetic#Definition_of_congruence_relation)