private void Register()
        {
            Console.WriteLine("Lets register you for Spacebook...");

            do
            {
                Console.WriteLine("All Spacebook names must  be unique.");
                Console.WriteLine("Type in a username: "******"Type in a password :"******"Thanks for registering with Spacebook.");
        }
        private bool Authenticate()
        {
            Console.WriteLine("Welcome {0}. Please type in your password.", name);

            string suppliedPassword = Console.ReadLine();

            if (suppliedPassword.Equals(password))
            {
                loggedIn = true;

                Console.WriteLine("Logged into Spacebook");

                if (mySpaceBook == null)
                {
                    mySpaceBook = new SpaceBook(name);
                }

                return(true);
            }

            Console.WriteLine("Incorrect password");
            return(false);
        }