CUPS, the Common UNIX Printing System, 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 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 (aka 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®. As a result, CUPS is ideally-suited for sharing and accessing printers in mixed environments of FreeBSD, Linux®, Mac OS® X, or Windows®.
The main site for CUPS is www.cups.org