What is the difference between a Window and Page item in a WPF project?
Windows are independent and normal WPF application windows like Forms in WinForm Application.
A window can contain WPF Pages using Frame Container.
Pages on the other hand are intended for use in Navigation applications, where we can navigate between pages from within a Window. Examples of Pages are in Wizard kind of applications where each screen in a wizard can be a page, which are hosted within the main wizard window. Pages are hosted in NavigationWindows or Frames.