1. An image formation system comprising: a data processing device configured to store print data in a portable storage medium, wherein the print data comprises page description language data; and an image formation device configured to form an image on a print medium in response to reading out the print data from the portable storage medium, wherein the data processing device comprises: a processor; and memory operatively coupled to the processor and storing computer readable instructions that, when executed by the processor, cause the data processing device to function as: a print data storing unit configured to store the print data in the portable storage medium; an image data generating unit configured to generate image data corresponding to the image to be formed on the print medium when the print data is read out, wherein the image data is of a different file format than the print data; and an image data storing unit configured to store the image data in the portable storage medium and to associate the image data with the print data stored in the portable storage medium, and wherein the image formation device comprises: a display unit configured to display an image corresponding to the image data stored in the portable storage medium; a selection unit configured to select the displayed image in response to a user operation indicative of a request to print the displayed image; and an image formation unit configured to form the image on the print medium based on the print data associated with the image data corresponding to the selected image.