DPOF 
Digital Print Order Format 
A standard specification that provides a simple mechanism for requesting prints from digital cameras. A DPOF-compliant camera can create a print order file that describes which shots should be printed, the quantity of prints desired, which thumbnails should be output as index prints, cropping and rotation settings, and user and picture information (names, descriptions, date stamp, and so on). The DPOF file is stored on the removable memory card, which allows you to either stick the card directly in a DPOF-compatible printer or send the files to a digital printing service.