Abstract: An image forming apparatus includes an image forming unit to form an image based on input printing data, a storage unit to store history information of the printing data therein, and a controller to determine whether the inputted printing data is already printed already by using the history information, and to control the image forming unit not to form the image with the printing data already used to form the image among the input printing data if it is determined that the printing data is already printed.

Abstract: An image processing apparatus including an extracting portion to extract a print object from print data based on a selection from list information included in the print data, an image processing portion to perform an image processing operation to output the print object and a controller to control the image processing portion to extract the print object based on the selection from the list information by a user, to select a layout corresponding to the extracted print object, and to output the extracted print object according to the selected layout.

Abstract: A method of generating extensible hypertext markup language (XHTML) data in a device generating XHTML data, the method including determining whether overlapping objects exist in XHTML data generated by the device; determining whether all of the overlapping objects have distinctiveness; and correcting a style of at least one overlapping object determined not to have distinctiveness among the overlapping objects.

Abstract: A method of indicating a paper insertion direction, the method including displaying an image of a paper cassette when a user tries to insert a paper on which other contents are previously printed into the paper cassette to print predetermined contents; displaying an expected print result indicating whether a to-be-printed side is on the same as a preprinted side of the paper and whether the to-be-printed side has the same up/down direction as the preprinted side; and displaying images that distinguish between front and rear sides of the paper and between up and down directions with respect to the preprinted side based on the expected print result.

Abstract: A method of indicating a paper insertion direction, the method including displaying an image of a paper box when a user tries to insert a paper on which other contents are previously printed into the paper box to print predetermined contents; displaying an expected print result indicating whether a to-be-printed side is on the same as a preprinted side of the paper and whether the to-be-printed side has the same up/down direction as the preprinted side; and displaying images that distinguish between front and rear sides of the paper and between up and down directions with respect to the preprinted side based on the expected print result.