Since I’ve been working in C++, I’ve noticed the necessity to get familiar with concepts about computer architecture and how the operating system works. One thing that has been bothering me for a few weeks is hearing people talk about the heap and stack memory, while I don’t really know what those things mean.
I decided to write this post to try to explain to myself what is the difference between stack memory and heap memory and hopefully understand why people keep talking about them.
Stack and Heap are both names of data structures. This can lead to some confusion, because although the stack is called like that because it works similar to a stack (I’ll explain more about this), the heap is not related at all to the heap data structure. The exact origin of the heap word in this context is unknown to me, but from a little research it seems like it’s use is based on the English language definition for that word:
An untidy collection of things piled up haphazardly
Which actually describes pretty well what a heap of memory is.