Basic Recursion

Recursive thinking refers to a problem-solving technique where the problem is broken down into smaller versions of the same problem.
Recursion is implemented in programming languages with method or functions that call themselves.
If methodA() calls methodB() whcih calls methodA(), ... that is also recursion.
The trick is to determine the stopping case(s), also called the base case, which is when the recursive calls stop.

N-Factorial is a classic recursive function.

    N! = N * (N - 1)!
    (N - 1)! = (N - 1) * (N - 2)!
    ...
    
In other words:

    N! = N * (N - 1) * (N - 2) * (N - 2) ... * (N - (N-1))

What is the stopping case?

Let's look at the code in recurse.cpp for a few code examples.
Each call in essence waits for the return of the recursive call, and then each call backs out returning their result.
Based on this descriptio, what data structure is used by the run-time environment to implement recursion?