1. In a data processing apparatus which is provided with a memory for storing document data including plural page data and display means for displaying the document data stored in said memory, a graphical user interface for editing the stored document data comprising: means for displaying an image of a plurality of graphical representations each representing a page data; means for displaying on the same image with said plurality of graphical represenations a graphical representation of a page designation means for designating one of said page data together with a cursor; means for moving the cursor within said graphical representation of the page designation means to designate an index representative of desired page data; means for reading out from said memory the page data corresponding to the index designated with the cursor; and means for displaying the read out page data on said display means.