Please help! I am trying to make an app, with the user setting their name so it can be later displayed on a label such as: Welcome, (username). But when trying to run my code, xcode gives me an error: Fatal error: Unexpectedly found nil while implicitly unwrapping an Optional value. Here is my code: class HomeViewController: UIViewController {     @IBOutlet weak var displayLbl: UILabel!     @IBOutlet weak var textField: UITextField!     @IBOutlet weak var submitBtn: UIButton!          var result : String!          override func viewDidLoad() {         super.viewDidLoad()                  displayLbl.text = ""                  submitBtn.setTitle("Submit", for: UIControl.State.normal)              }          @IBAction func submitAction(_ sender: Any) {                  result = textField.text!         displayLbl.text = "\(result!)"              }      It gives me an error on (displayLbl.text = ""), but I don't know what to do about it. Please help