What is stream?

Question

I don't understand it

Answer 1

thereis a structure of c++ right. wh at is it?

Answer 2

Just regard:
#include <iostream>
as a necessary invisible heart.
It's beating, but it can't be seen.
The iostream is a library (important stuff) which every program imports/includes to use standard functions.

So: do not comment or delete it. break;

edit 0
Yes, there is a structure to the language, which would take too long to explain. Search on the internet for a guide to C++ and it will certainly tell you indepth about the meanings and actions of different bits/bobs.
#include <iostream> is an imperative statement to include another document of code in yours: it's a "commander", if you would see it as that.