Check out example codes for "hello world c#". It will help you in understanding the concepts better.

Code Example 1

// Hello World! program
namespace HelloWorld
{
    class Hello {         
        static void Main(string[] args)
        {
            System.Console.WriteLine("Hello World!");
        }
    }
}

Code Example 2

Console.WriteLine("Hello World!");

Code Example 3

using System;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello, world!");

            // To prevents the screen from  
            // running and closing quickly 
            Console.ReadLine();
        }
    }
}

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