An Acronym for Internet Printing Protocol.
A protocol designed to easily allow computers to communicate both with IPP-enabled printers, and with computers acting as print servers. It uses HTTP on Port 631 (listed in services(5)) -- programs send HTTP POST requests to print and use special URLs to query the spool service. Pointing your WebBrowser at http://localhost:631/ should reveal a web interface to the spool service where you can view the printers available on your machine, including remote printers and print servers that your local machine is set up to use.
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