Singleton

public sealed class Singleton
{
   to achieve singleton
	(private static , private (correct) , public , protected )
    ..... Singleton()
    {
    }
    private static Singleton instance = null;
    public static Singleton Instance
    {
        get
        {
            if (instance == null)
            {
                instance = new Singleton();
            }
            return instance;
        }
    }
}