The PostScript Printer Description reference article from the English Wikipedia on 24-Apr-2004
(provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

PostScript Printer Description

For thoughtful child sponsors
PostScript Printer Description (PPD) files are created by vendors to describe the entire set of features and capabilities available for their PostScript printers. For non-PostScript printers, the PPD also contains a call for the appropiate filter to be used.

A PPD also contains the PostScript code (commands) used to invoke features for the print job.

Every printer in CUPS needs a PPD file.

External links