What is a Call Stack?

In programming, a call stack is a last-in, first-out listing of procedure calls.

Real World Analogy

My wife has a question for my son, Luke, but he's off in the woods.  So the question gets relayed through the whole family:

Unwinding the Stack

As each person responds, the stack shrinks:

Viewing the Call Stack

To view the call stack in VBA, go to View > Call Stack... (Ctrl + L).  

Note that the call stack window is only available while the code is executing.

Image by PublicDomainPictures from Pixabay

UPDATED [2021-11-05]: Added sample code to the VBA Call Stack screenshot; added image credit.