(1) System software that schedules, queues and spools printer output from an application to the printer. In modern operating systems, applications communicate with the printing system via a programming interface (API). The printing system causes the output to be converted into a printer language such as PostScript, PDF and PCL or formatted as final output in the form of a bitmap (rasterized).

The printing system comprises the printer driver, which includes the commands required by the specific printer. In the case of host-based printing, the pre-rasterized pages (turned into bitmaps) and print head commands are sent to the printer (see host-based printing).

Windows Print Manager and CUPS
The two major printing system are the Windows Print Manager for Windows and the Common Unix Printing System (CUPS) for Linux/Unix and Mac. Note that the Windows Printing System is a host-based printing function that works with the Windows Print Manager. See Windows Print Manager, Windows Printing System and CUPS.

(2) An assembly of computers and printing equipment that turns print jobs into printed output.