Hello World! I'm going to explain the Hello World program in C++.
The first line begins with //
The // indicates that the compiler should ignore everything until the end of the line.
This is called a comment. 
A comment is a way for a programmer to leave notes for himself.
The next 2 lines are preprocessor directives.
When we run this program, it's going to compile.
Before it compiles, it will include the input output stream.
You're going to need this for just about every program you write in C++.
The next line says using namespace std; STD stands for "standard"
If we didn't have this line, every statement that says cout, would first have to say std::
You may see that format on some web pages and in some books, 
And then they don't use using namespace std;
I'm going to keep it simple and use namespace std;

When we run the program, execution will always start with a function called main.
main is going to return an integer,
But it has no parameters or arguments.
That's why it says void.
The body of the function is enclosed inside curly braces { }
Your programs are going to have a lot of curly braces.
It's a good idea to use a comment to label those closing curly braces.

The first statement inside function main is cout: that stands for console output.
We are going to send the string "Hello World\n" to the console.
We have a backslash n, \n, 
That is an escape sequence. 
That means that after writing Hello World it will do a line feed, or go to a new line.

You'll notice that every statement ends in a semi-colon ;
Here's another one, and another one...

The next statement says system("pause"); 
What that's going to do is make the console window stay open, 
Instead of just closing immediately.
You will see a message that says "Press any key to continue"

After we press any key to continue,
It says return 0; 
Remember, main is going to return an integer?
Here a zero is returned meaning that 0 errors occurred.
If we get to that point.
And that's the end of main.

We will see that output when we run it.
You will see it says Hello World, and then it went to a new line.
And then the system pause message: Press any key to continue.
Press anything and we go back to the program.