Stack Vs Heap

Stack variables are automatic local objects, while heap objects are requested and released explicitly.

stack_vs_heap.c

#include <stdio.h>
#include <stdlib.h>

int main(void) {
    int stackValue = ;
    int *heapValue = (int *)malloc(sizeof(int));

    if (heapValue == 0) {
        return 1;
    }

    *heapValue = stackValue + 1;

    printf("stack=%d heap=%d\n", stackValue, *heapValue);
    free(heapValue);
    return 0;
}

#include <stdio.h>
#include <stdlib.h>

int main(void) {
    int stackValue = ;
    int *heapValue = (int *)malloc(sizeof(int));

    if (heapValue == 0) {
        return 1;
    }

    *heapValue = stackValue + 1;

    printf("stack=%d heap=%d\n", stackValue, *heapValue);
    free(heapValue);
    return 0;
}

#include <stdio.h>
#include <stdlib.h>

int main(void) {
    int stackValue = ;
    int *heapValue = (int *)malloc(sizeof(int));

    if (heapValue == 0) {
        return 1;
    }

    *heapValue = stackValue + 1;

    printf("stack=%d heap=%d\n", stackValue, *heapValue);
    free(heapValue);
    return 0;
}

stack value `stackValue` is a normal local variable with automatic lifetime.

heap value `malloc` creates heap storage that must later be released with `free`.