Modal and non modal dialog boxes

In general, in Windows applications, dialogs are divided into modal dialog boxes and non-modal dialogs. The difference is whether the user is allowed to manipulate other objects while the dialog box is open.
Modal dialog boxes monopolize the user's input. When a modal dialog box is open, the user can only interact with the dialog box, while other user interface objects cannot receive input information. Modal dialog box, the user needs to manipulate the modal dialog box before the Action Target dialog box is required.

Modeless Dialogs (Nonmodal dialogue box, also known as modeless dialogs), unlike modal dialogs, can still manipulate other windows when the user opens a modeless dialog box.

Modal and non modal dialog boxes