9. A non-transitory computer-readable storage medium storing a document managing program instructions for: storing an order of a plurality of documents constituting management objects; generating image data including representative image data in a specified data format for each document; storing the image data generated; detecting a fluctuation amount input into an input device; determining the order of the document to be displayed in a display which displays the image data stored based on the fluctuation amount detected, if detection of the fluctuation amount input is during a state in which image data of a document is displayed in the display; and switching the image data of the document displayed in the display to the representative image data of the document having the order determined.
9. A non-transitory computer-readable storage medium storing a document managing program instructions for: storing an order of a plurality of documents constituting management objects; generating image data including representative image data in a specified data format for each document; storing the image data generated; detecting a fluctuation amount input into an input device; determining the order of the document to be displayed in a display which displays the image data stored based on the fluctuation amount detected, if detection of the fluctuation amount input is during a state in which image data of a document is displayed in the display; and switching the image data of the document displayed in the display to the representative image data of the document having the order determined. 12. The non-transitory computer-readable storage medium according to claim 9 , wherein the representative image is a whole image of a representative page in each document.