CUPS provides a portable printing layer for UNIX-based operating
systems. It has been developed by Easy Software Products to promote a
standard printing solution for all UNIX vendors and users. CUPS
provides the System V and Berkeley command-line interfaces.

CUPS uses the Internet Printing Protocol ("IPP") as the basis for
managing print jobs and queues. The Line Printer Daemon ("LPD") Server
Message Block ("SMB"), and AppSocket (a.k.a. JetDirect) protocols are
also supported with reduced functionality. CUPS adds network printer
browsing and PostScript Printer Description ("PPD") based printing
options to support real-world printing under UNIX.

CUPS also includes a customized version of GNU Ghostscript (currently
based off GNU Ghostscript 5.50) and an image file RIP that are used to
support non-PostScript printers. Sample drivers for HP and EPSON
printers are included that use these filters.

- George Reid
greid@ukug.uk.freebsd.org