To display an HTML document on a display (51), a browser interprets only display tags and ignores print tags. To interpret the tags and display the HTML document, the browser transmits a request for transferring four image files (A1, B1, C1, and D1) to a WWW server (40) and displays the image files on the display (51). When the user clicks on a print button displayed on the display (51) by the browser, the browser interprets tags used for print, transmits a request for transferring four image files (A2, B2, C2, and D2) to the WWW server (40), and prints the four image files on a printer (80).