Comment ALL the Things!

Below is the complete code for the Comment ALL the Things! Try It Out! problem, adding comments of different types to the original Hello World program.

// Using directives tell the compiler where to find piles of existing code. 
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

/* A namespace is the largest way to organize code, gathering them 
 * into large containers of related code.
 */
namespace HelloWorld
{
    /* A class is a way of packaging up related data and methods that use
     * that data all together into one reusable piece of code.
     */
    class Program
    {
        // A method like this Main method is the smallest way to package a chunk 
        // of code together. A method is usually supposed to accomplish only a 
        // single, specific goal. Note that these "single line" comments can be 
        // used to create multi-line comments, and in fact, this is the way most 
        // C# programmers do it.
        static void Main(string[] args)
        {
            // Prints out the text "Hello World!" to the screen.
            Console.WriteLine("Hello World!");
            
            // Waits until the user presses any key before finishing the program.
            Console.ReadKey();
        }
    }
} // Curly braces like this usually mark the beginning and ending of blocks of  
  // code. You can see that curly braces are used here to start and end methods,
  // classes, and namespaces.