Making of Program: A note on Stack and Heap

Stack-memory and Heap-memory are physically the same.
The RAM may be used as stack memory when running one program and later used as heap memory when running some other program.
The difference is in how they are used.

Difference between Stack vs Heap memory:

Stack:

Often a function or method calls another function which in turn calls another function etc.
The execution of all those functions remains suspended until the very last function returns its value.
All the information required to resume the execution of these functions is stored on the stack.

Local variables are often stored for short amounts of time while a function/method block uses them to compute a task.
Once a function/method has completed its cycle, the space on the stack used by all local variables is freed.

This chain of suspended function calls is the stack, because elements in the stack (function calls) depend on each other.
The stack is important to consider in exception handling and thread executions.

Heap:

The heap is simply the memory used by programs to store global variables. or All global variables are stored in heap memory.
Element of the heap (variables) have no dependencies with each other and can always be accessed randomly at any time.
All variables dynamically created by the program with "new()" or "malloc()" or similar commands are also stored on the heap.
In some programming languages, all instances of an object, including all the attributes of that instance, are stored on the heap (java).
In those programming languages, local variables of a function that have object type are implemented as creating the new object on the heap, and storing a reference to that object in the local variable, which is on the stack.
When that function exits, the heap memory used by each local variable that has object is freed, and then all the stack used by that stack is freed.

Similarties:

Making of Program