How does dynamic variable get stored in memory? is it heap or stack?

Stack and Heap are just general terms, I mean theories, as long as the program executes it is the RAM that handles the things. Memory means memory it has no name like stack and heap.

Stack is for anything that is predecided in size(primitive datatypes, ) as the name suggests it should always be for continuous memory locations, so there might be some continuous block of memory for some variables and addresses of Objects.

 A heap is any memory that is allocated dynamically and randomly.

In reality, memory can be allocated in any fashion, and in modern OS and processors it is very abstracted, so how is it taking memory is difficult to know.  

But one thing is clear that for dynamic things the area reserved dynamically and anywhere in ram is termed as a heap. while for static things, the contiguous memory locations, we call it stack.

and for obvious reasons, the stack will be faster.