A print processor or a printer driver, in computers, is a program that translates the data to be printed to the form particular to the printer. The goal of a printer driver, such as HP envy 4500 driver, is to enable apps to print without being aware of the technical information of every model of printer.

Keep in mind that printer drivers must not be mixed up with print spoolers. These are the software that queue print tasks and successively send them to the printer.

UNIX

UNIX systems, like OS X and Linux, utilize Common UNIX Printing System (CUPS). This is an integrated printing system for UNIX-like computer OS. This enables a computer to act as a host for printing. A computer operating CUPS is a server that could accept print tasks from computers, operate them, and send them to the suitable printers.

DOS

DOS supports character devices PRN that are predefined, such as LPT3, LPT2,  and LPT1, that are connected with parallel printers reinforced in its system. Likewise, serial printers could be utilized with AUX such as COM4, COM3, COM2, and COM1.

Also, DOS offers a print spooler that is dynamically loadable. It is called PRINT. It also offers optional support to reinforce screen captures.

Windows

Printer drivers of Windows use XPS (XPSDrv) or GDI (PScript or Unidrv-based). Software then utilizes the similar regular APIs to draw pictures and text both on paper and on screen. Printers that natively utilize GDI are usually called Win printers and are typically not compatible with other OS.

Amiga

The Amiga OS 1.3 up to the original one supported printers via a regular sequence of drivers stored at “DEVS:Printers” the required path of the OS. Each printer driver was kept in that location, and supported the regular printers in circa 1985 up to 1989.