A method for displaying a plurality of windows on a display screen is described. The method includes steps of associating a first window with a second window, where the second window is independent of the first window, arranging the first window and the second window on a display screen, where the first window and the second window are configured to fit within a predetermined region of the display screen, and notifying an application program corresponding to the first window that the second window is associated with the first window. An indicator may appear on the display as a target region when a user desires to associate the first and the second windows. Subsequent operations performed on the first window are performed automatically on the second window. For example, when a user is comparing two documents, she can scroll down one document and have the second document automatically scroll as well.