Please note that the content of this book primarily consists of articles
available from Wikipedia or other free sources online. In computers, a
printer driver or a print processor is a piece of software that converts
the data to be printed to the form specific to a printer. The purpose of
printer drivers is to allow applications to do printing without being
aware of the technical details of each printer model. Printer drivers
should not be confused with print spoolers, that queue print jobs and
send them to printer one after the other. On UNIX systems and other
systems which use the Common Unix Printing System, such as Mac OS X,
printer drivers are typically implemented as filters. They are usually
named the front end of the printing system, while the printer spoolers
constitute the back end. Backends are also used to determinate the
available devices. On startup, each backend is asked for a list of
devices it supports, and any information that is available.
