Actually, that explanation is a bit lacking.
The % sign in most common programming languages is modulo
Remember when you first learned to divide, we would go "5 divided by 2 = 2 remains 1"
Modulo is that "remains x".
So yes, it will wrap around the values, but it has a lot of other super useful uses.
Some quick examples:
4 % 3 = 3
4 % 2 = 0
5 % 6 = 5
5 % 0 = error