A dialog box is a secondary window that allows users to perform a command and provides users with information or progress feedback.

Dialog boxes have two fundamental types:

Modal dialog boxes require users to complete and close before continuing with the owner window. These dialog boxes are best used for critical or infrequent, one-off tasks that require completion before continuing.

Modeless dialog boxes allow users to switch between the dialog box and the owner window as desired. These dialog boxes are best used for frequent, repetitive, on-going tasks.

Dialog boxes consist of a title bar (to identify the command, feature, or program where a dialog box came from), an optional main instruction (to explain the user's objective with the dialog box), various controls in the content area (to present options), and commit buttons (to indicate how the user wants to commit to the task).

They consist of the following parts:

• A title bar to identify the application or system feature where the dialog box came from.
• A main instruction, with an optional icon, to identify the user's objective with the dialog.
• A content area for descriptive information and controls.
• A command area for commit buttons, including a Cancel button, and optional more option.
• A footnote area for optional additional explanations and help.