For example, to merge a graphic form with the data stream requires an understanding of PostScript commands according to the Adobe PostScript Language Reference Manual (PLRM, otherwise known as the "Red book"). Xerox gives you this feature through this simple command "(formname) SETFORM", where formname is the name of the form accessible from the Xerox printer controller (DocuSP or FreeFlow Print Server). Several VIPP commands are identical to PostScript commands.
