Raster Graphics

Printer Driver

A printer driver is a program that translates the file you are printing into a language that the printer understands. Usually, the printer driver is installed within an application.

PROM

An acronym for Programmable Read-Only Memory. A storage device that can be programmed by electrical pulses, a PROM does not lose its memory when the printer is powered off. See also EEPROM, EPROM.

Protocol

A set of rules or standards designed to enable computers and other devices to connect to one another and to exchange information.

Queue

A list of documents waiting to be printed.

RAM

An acronym for Random Access Memory, the memory your printer uses to perform tasks. It can be written to and read from. Once a task is complete, the memory is free again to be used for another file. This memory is volatile, so if your printer loses power while a file is being sent, you must resend the file. The number and type of features you can run simultaneously on your printer depend on the amount of RAM available and how that RAM is distributed. RAM can be increased by adding SIMMs. See also SIMM.

RAM Disk

Also called a virtual disk. The RAM disk is an area of RAM that is used to simulate an additional hard disk. Data can be written to and read from a RAM disk more quickly than a hard disk, but a RAM disk loses any information stored on it when the printer’s power is turned off. The frame buffer and spooling buffer are RAM disk clients. See also RAM.

Raster Graphics

The system of forming graphics using a bitmap, or grid of small dots, is called raster graphics. The term “raster” denotes the Cartesian grid system in which the dots are arranged. Bitmaps can define images, shapes, or characters created with a specific number of dots per inch. See also bitmap.

Glossary

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