Use the system thread pool : ThreadPool « Thread « C# / CSharp Tutorial

using System;
using System.Threading;

class MainClass
{
  public static void Countdown(Object o) 
  {
    for (int i = 1000; i > 0; i--) 
    {
      Console.Write(i.ToString() + " ");
    }
  }

  public static void Main() 
  {
    ThreadPool.QueueUserWorkItem(new WaitCallback(Countdown), null);
  }
}

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20.28.ThreadPool
	20.28.1.	Thread Pool Example
	20.28.2.	Use ThreadPool
	20.28.3.	Using the thread pool and no arguments
	20.28.4.	Using the thread pool and providing an argument
	20.28.5.	Use ThreadPool to implement a hello server
	20.28.6.	Use the system thread pool
	20.28.7.	Registering wait callbacks for events
	20.28.8.	Available worker/IO threads
	20.28.9.	Max worker/IO threads in a ThreadPool
	20.28.10.	Min worker/IO threads in a ThreadPool
	20.28.11.	Scheduling work to occur on the thread-pool
	20.28.12.	ThreadPool Demo
	20.28.13.	Using ThreadPool Instead of Instantiating Threads Explicitly
	20.28.14.	Queuing a task for execution by ThreadPool threads, with the RegisterWaitForSingleObject method.
	20.28.15.	QueueUserWorkItem and RegisterWaitForSingleObject: Queue a task, represented by the ThreadProc method, using the QueueUserWorkItem method.
	20.28.16.	Canceling a queued task with RegisteredWaitHandle.
	20.28.17.	Use the QueueUserWorkItem method to queue a task and supply the data for the task.