This property is not relevant for this class.

If a form is a child of another form, the child form is not displayed in the Windows taskbar.

You can use this property to prevent users from selecting your form through the Windows taskbar. For example, if you display a Find and Replace tool window in your application, you might want to prevent that window from being selected through the Windows taskbar, since you would need both the application's main window and the Find and Replace tool window displayed in order to process searches appropriately.