To Create Printer output CRTPRTF , a program, OS/400 utility, or print-key function must write the output data to a printer file. A printer file is a type of device file that determines what attributes printed output will have. It defines the formatting, page size and special printing features. Moreover it may specify an output queue.
Users can use CRTPRTF (Create Printer File) command to create new printer files for any special reports or printing conditions. However numerous IBM-supplied printer files are available for general purpose printing and system utilities.
If the printer file does not specify another output queue, then the output queue currently assigned to the job will be used.
Spoolers use queues to temporarily hold printed output from various programs. Each item of printed output represents a single report, program compile, print screen operation, and so on, and each of these is called a spooled file.
Spooled files are “Printed output” in the sense that they are formatted and ready to print; but until they are written to a physical printer device they exist only as a collection of bits on magnetic storage media.
You can think of output queues as areas of secondary storage managed by the spooler that can grow or shrink in size as more spooled files pile up in the queue or are sent off to a physical printer device.