//No database is connected. Variables are stored in memory at runtime using System; namespace ConsoleApp1 { internal class Program { //variables are created globally. coz need to use in multiple methods. static string userName, password; public static void Main(string[] args) { Register(); Login(); } //register() public static void Register() { Console.WriteLine("---------- Registration ---------"); Console.WriteLine("User name: "); userName = Console.ReadLine(); Console.WriteLine("Password: "); password = Console.ReadLine(); Console.WriteLine("Registration successfull"); Console.WriteLine(); } //login public static void Login() { Console.WriteLine("User name: "); if (userName == Console.ReadLine()) { Console.WriteLine("Password: "); if (password == Console.ReadLine()) { Console.WriteLine("Login Successful"); } else { Console.WriteLine("Invalid Password"); } } else { Console.WriteLine("Invalid User name !"); } } } }