On 10.11-17:01, Predrag Punosevac wrote: [ ... ] > >PPD files are post script description files that act as a drivers for > >post script printers. This seems clear to me.
no. they simply describe the functions available on the printer. this allows the interface to display those printer options to you. for PS compatible printers this is enough, you select the options and the document, with the selected options, are passed along to the printer. for non-PS printers the options are passed to the backend processor which produces the relevant commands for that printer. with CUPS you'll (most likely) have ghostscript as a backend processor. this comes with support for a good range of printer backends (e.g. PCL) as well as being easily extensible with vendor processors (like the hpijs processor from HP). with lpd and apsfilter you process the incoming text or latex file into postscript. this works fine if the printer supports PS. if not then you'll pipe that postscript onto ghostscript which will then process the PS into the native printer language (e.g. PCL).
