Use of {0} and comments - Tutorial C# Sharp

using System;
public class Multiplication
{
    public static void Main()
    {
        int number1, number2, number3;
        Console.Write("Enter the first number to multiply: ");
        number1 = Convert.ToInt32(Console.ReadLine());
        Console.Write("Enter the second number to multiply: ");
        number2 = Convert.ToInt32(Console.ReadLine());
        Console.Write("Enter the third number to multiply: ");
        number3 = Convert.ToInt32(Console.ReadLine());
        int result = number1 * number2 * number3;
        Console.WriteLine("Result: {0} x {1} x {2} = {3}", number1, number2, number3, result);
    }
}