using baground thread in c#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace ConsoleApplication7
{
    class Program
    {
        public static void Main()
        {
            System.Threading.Thread t = new Thread(threadmethod);
            t.IsBackground = true;
            t.Start();
            for (int i = 0; i < 4; i++)
            {
                Console.WriteLine("Main thread proc {0}",i);
                System.Threading.Thread.Sleep(500);
            }
         
        }
        public static void threadmethod()
        {
            for (int i = 0; i < 10; i++)
            {
                Console.WriteLine("Thread method proc {0}",i);
                System.Threading.Thread.Sleep(500);
            }
        }

    }
}
result:
if u set background property true thread exits Immediately 
Main thread proc 0
Thread method proc 0
Main thread proc 1
Thread method proc 1
Thread method proc 2
Main thread proc 2
Thread method proc 3
Main thread proc 3
Thread method proc 4
Press any key to continue . . .

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