CUPS

Not Plastic Cups but the Printsystem CUPS

CUPS, the Common Unix Printing System, allows a computer to act as a print server.
CUPS is the software you use to print from applications like the web browser you are using to read this page.
It converts the page descriptions produced by your application (put a paragraph here, draw a line there, and so forth) into something your printer can understand and then sends the information to the printer for printing.
A computer running CUPS is a host that can accept print jobs from client computers, process them, and send them to the appropriate printer.

History:

Michael Sweet, who owns Easy Software Products, started developing CUPS in 1997.
The first public betas appeared in 1999.
The original design of CUPS used the LPD protocol, but due to limitations in LPD and vendor incompatibilities, the Internet Printing Protocol (IPP) was chosen instead. CUPS was quickly adopted as the default printing system for several Linux distributions, including Red Hat Linux.
In March 2002, Apple Inc. adopted CUPS as the printing system for Mac OS X 10.2.
In February 2007, Apple Inc. hired chief developer Michael Sweet and purchased the CUPS source code.

How Does It Work?

The first time you print to a printer, CUPS creates a queue to keep track of the current status of the printer (everything OK, out of paper, etc.) and any pages you have printed.
Most of the time the queue points to a printer connected directly to your computer via a USB or parallel port, however it can also point to a printer on your network, a printer on the Internet, or multiple printers depending on the configuration.
Regardless of where the queue points, it will look like any other printer to you and your applications.

Every time you print something, CUPS creates a job which contains the queue you are sending the print to, the name of the document you are printing, and the page descriptions. Job are numbered (queue-1, queue-2, and so forth) so you can monitor the job as it is printed or cancel it if you see a mistake. When CUPS gets a job for printing, it determines the best programs (filters, printer drivers, port monitors, and backends) to convert the pages into a printable format and then runs them to actually print the job.

When the print job is completely printed, CUPS removes the job from the queue and moves on to any other jobs you have submitted. You can also be notified when the job is finished, or if there are any errors during printing, in several different ways.

Acces to Webinterface:

CUPS provides a web interface (which is sometimes called a GUI, although we rely on the web browser to provide the graphical part) that allows you to view print jobs, printers, and the online help, as well as manage your printers.

The CUPS web interface is available on your machine at the following URL:

http://localhost:631

Some pages require a username and password to perform certain actions, for example to add a printer. In general you can use your login name and password, but on Mac OS X your login name is called the “short user name” which is usually your first and last name in lowercase. For example, if your name is “John Doe”, your short username would be “johndoe”.

Links:

www.cups.org/
en.wikipedia.org/wiki/CUPS

http://blogs.sun.com/DanX/entry/using_cups_print_server_for

This cowers CUPS for this time !