Printing Terms Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X-Y-Z
DARPA: See Defense Advanced Research Projects Agency.
Data: According to AT&T Bell Labs: Data is "A representation of facts, concepts or instructions in a formalized manner, suitable for communication, interpretation or processing."
Data Communications: The movement of data between points, including all the manual and machine operations necessary for this movement. Contrast with data transfer.
Data Content Model: SGML-speak for the occurence notation that describes what other markup is legal within the context of a specific markup element.
Data Compression: Reducing the amount of electronic "space" data takes up. Methods include replacing blank spaces with a character count, or replacing redundant data with shorter stand-in "codes". No matter how data is compressed, it must be decompressed before it can be used.
Data File: Any file created within an application: a word processing document, a spreadsheet, a database file, a chart, etc. Also known as a document.
Data Frame: The structured packets into which data is placed by the Data Link Layer.
Datagram: a packet of information and delivery data that is routed on a network.
Data Shift: In color process printing, it describes a shift in one of the channels of data that comprise the image file and could cause inconsistent color in some area of the image.
Data Transfer: The movement of data inside a computer system.
Database: Data that has been organized and structured in a disciplined fashion, so that access to information of interest is as quick as possible. Database management programs form the foundation for most document storage indexing systems.
DBMS: Database Management System. A complex system of programs and utilities used to define, maintain, and manage access to large collections of online data.
DCS: Desktop Color Separation. Developed by Quark. A DCS file is composed of five files. The main file is a composite with pointers to separation files and a low-resolution PICT preview file. There are four separations files, one for each process color.
DDCP: Direct Digital Color Proofing, a prepress proofing method which creates color proofs without the need for film or plates by using only digital data.
DDES: Digital Data Exchange Standards, a set of established formats, protocols, and values allowing one vendor's equipment to exchange data with another vendor's equipment. In color process printing, data can be exchanged between Color Electronic Prepress Systems.
Debug: The process of detecting, locating, and removing mistakes or malfunctions from newly developed software or hardware components of a computer.
Decompress: To reverse the procedure conducted by compression software, and thereby return compressed data to its original size and condition.
Decrement: In color process printing, it describes the decrease of a brightness, hue, or saturation value in an image.
Dedicated Device: A piece of hardware that is permanently assigned to one task. The task, however, can be changed by reprogramming or by the introduction of different software.
Dedicated System: Describes the permsnent assignment of an entire electronic system to one task.
Defense Advanced Research Projects Agency:
An agency of the U.S. Department of Defense that sponsored the development
of the protocols that became the TCP/IP suite. DARPA was previously known as
ARPA, the Advanced Research Project Agency, when ARPANET was built.
Degausser: A device that removes unwanted magnetism from monitors
or the heads in a tape or disk drive mechanism.
Delete: Describes the action of discarding data from memory or
storage.
Delimiter: The "divider" character, often a comma, between
separate fields in database records. It is a special character that
indicates a record or field boundary within a text stream, rather than being
interpreted as an actual part of the text itself.
Demilitarized Zone (DMZ):
Computer slang used for a protected network that sits between
the Internet and the corporate network.
Densitometer: In photography, a sensitive photoelectric instrument
which measures the density of photographic images or of colors.
In lithography, a reflection densitometer is used to measure
the density of the ink colors to determine they are consistent
throughout the run. A transmission densitometer can be used to
check reproduction dot sizes in order to maintain quality assurance
in color. Both measure optical density and are considerably more
sensitive and accurate than is the human eye.
Density: A measure of the relative difference between a white
area and a toned or black area. Can be applied both to black
and white and color. Or the ability of a material to absorb light.
It is inversely proportional to the amount of light reflected
or transmitted through the sample.
Descenders: A typographic term for the portion of lowercase characters
that falls below the main body of the letter. The lower case letters
g, j, p, q and y have descenders.
Desktop: Slang for any computer function that can be done on a
standalone PC, rather than a larger, more powerful, computer.
Desktop Publishing: The term applied to the creation of printed
documents using a PC. The documents may be printed directly from
the desktop publishing application software (usually with a desktop
laser printer), or prepared for a commercial printing process.
Do not confuse with "electronic publishing," which refers
to electronically preparing documents which are to be read by
electronic means.
Detail Contrast: In electronic scanning, the ability to increase
the apparent detail contrast from light to dark and from dark
to light by simple electronic manipulation. This produces an
increased visual contrast on edge sharpness, thereby enhancing
the image. The particular control section of a scanner that carries
out this particular function is the unsharp masking area (USM).
Developing agent: The chemical in a photographic developer that
converts exposed silver halide to visible black metallic silver.
Device: Any gadget that is plugged into a computer. May also
be reffered to as an "external device." Examples are
disk drives, video monitors, keyboards and printing devices.
Device Driver: A miniture program that acts like a translator,
converting the output from one device into data that another device
can understand. For example, a PC-compatible needs a device driver
before it can understand the signals from a mouse; and a Macintosh
needs a device driver in order to interact with a fax-modem.
Device Independent: A program or file format that can be used
with two or more different computing devices and produce identical
results. For example, a page saved in PostScript format should
be printable on an HP LaserPrinter IV or on a Linotronic output.
device.
Dialog Box: A rectangular box that either requests or provides
information. Many dialog boxes present options to choose from
before Windows can carry out a command. Some dialog boxes present
warnings or explain why a command can't be completed. ˜
Differential Spacing: In typography, allowing letters to take
up varying horizontal space in relation to their widths. For example,
and "i" takes up less space than an upper-case "W".
Opposite of fixed spacing, where each letter is assigned the same
space, regardless of its shape or width.
Digital: The use of binary code to record information. "Information"
can be text in a binary code like ASCII, or scanned images in
a bit mapped form, or sound in a sampled digital form, or video.
Recording information digitally has many advantages over its analog
counter part, mainly ease in manipulation and accuracy in transmission.
Digital Camera: The newest generation of video cameras transform
visual information (lightness and darkness) into pixels, then
translate the pixel's level of light into a number (or, in the
case of color, into three numbers _ one for the level of red,
green and blue in the pixel). These digital images can then be
manipulated pixel by pixel to create exciting new applications
in video and film production. They can also be compressed, stored
and transmitted in more or less the same manner as traditional
digital data.
Digital File: A art file that resides on disk, usually in a native application
format. See also CREF.
Digital Proof: A proofing system that does not include
the use of film. Data is sent to a printer and imaged directly onto a paper-based
material. There are several limitations of a digital proof: 1)they do not use
the film that will be used to produce plates, and thus are open to
interpretation of the output device, 2)few of these devices print in the
same dot pattern as is utilized in the printing process, and 3)the ink
utilized in these printers is not representative of the inks used in the printing
process and can show a vast color range and density not attainable on a printing press.
Digitize: To convert an image or signal into binary code. visual
images are digitized by scanning them and assigning a binary code
to the resulting vector or raster graphics data. Sounds are digitized
by recording frequent "samples" of the analog wave,
and translating that data into binary code.
Dipthong: In typesetting, two vowels which are joined to form
a single character, also known as digraph. A special form of ligature.
Direct Image Film: Film that maintains the same polarity _ positive
for positive, negative for negative _ as the image which it is
duplicating.
Disc: Same as optical disc. A digital storage medium. Optical
discs are made of a metal alloy recording surface sandwiched between
a rigid substrate and a plastic protective coating. Lasers record
data in the metal alloy by either creating tiny pits (ablation
technique) or by causing small bubbles to form in the "negative"
area, thereby reflecting the laser away. Generally, and in this
dictionary, disc with a "c" means optical disc. Disk
with a "k" means magnetic hard or floppy disk.
Disk: Same as magnetic disk. A round, flat magnetic recording
medium with one or more layers deposited on the surface which
data can be recorded onto.
Disk Drive: A device containing motors, electronics and other
gadgetry for storing (writing) and retrieving (reading) data on
a disk. A hard disk drive is one which is generally not removable
from the machine. A floppy disk drive accepts removable disk cartridges.
Disk Operating System: Often abbreviated as DOS, a kind of low-level
program which has to be present in the computer's memory at all
times while the computer is running, in addition to any other
programs that are being used. The system (known as DOS in PC-compatibles
or The Finder on a Macintosh) manages all disk operations.
Disk Pack: A grouping of magnetic disks, resembling a stack of
phonograph records, offering large capacity information storage.
Disk Space: The amount of bytes on a disk available for recording
or storing data.
Display PostScript: The PostScript command set that renders images
directly to the screen.
Display Type: Used for headlines and advertising copy, it is larger
than 14 points.
Dithering: Simulating gray tones by altering the size, arrangement
or shape of background dots.
DLL: See Dynamic Link Library.
DNS: Domain Name Service. An Internet service that maps
sybolic names to IP addresses by distributing queries among the
available pool of DNS servers.
Domain: For DNS, a group of workstations and servers that share
a single group name.
Dot: The individual element of a halftone. Its size (density)
can be related to the density of the original used to produce
the halftone dot. The size of the dot is indicated by the percentage
of the area it occupies from zero to on hundred percent. It may
be several shapes including round, square or elliptical.
Dot Etching: In lithography, the chemical etching of silver halide
halftone emulsions to increase or reduce the amount of color to
be produced. Dot etching negatives increases color; dot etching
positives reduces color.
Dot Gain: An increase in the size of halftone dots that may occur
as a result of errors or imperfections in any of the steps between
screening an image and printing it onto paper. Common causes
of mechanical dot gain are incorrect plate exposure, excessive
tack or incorrect viscosity of printing ink, excessive ink film
thickness, internal reflection of the ink, or too much preasure
between the blanket roller and the impression cylinder.
Dot Pitch: The distance of one phosphor dot in a CRT to the nearest
phosphor dot of the same color on the adjacent line.
Dot Spread: In printing, a defect in which dots print larger
than they should, causing darker tones or colors. (See dot gain)
Double Burn: The merging of two films into one using a contact
screen camera. It is usually used to bring the black text into
the black separation.
Download: The transfer of data from a computer or telecommunications
network to another electronic device or storage medium.
DPI: Dots Per Inch. A measurement of output device resolution
and quality. Measures the number of dots a printer can print per
inch both horizontally and vertically. A 600 dpi printer can print
360,000 (600 by 600) dots on one square inch of paper.
Dr. Web:
A group of dedicated individuals who answer
Web-related questions about the Web through a Web screen.
Drag: A function of the mouse by which an element on the screen
of a monitor is moved with the cursor, while holding down the
mouse button and moving the mouse.
Drop Capital: At the beginning of a paragraph, the initial capital
letter can be modified to make a drop capital bydescending the
letter below the baseline of the first line of text.
Drum: The common name for the photoconductive cylinders used
on scanners and plotters.
Dry Processing: Method in which an exposed latent image is made
visible without chemical treatment (usually a heat process.
Dry Silver Film: Thermal process film. A non-gelatin silver film
type which is processed by heat, not chemicals.
Dummy: a preliminary layout showing the position of illustrations
and text as they are to appear in the final reproduction. A set
of blank pages made up in advance to show the size, shape, color,
form and general style of a piece of printing.
Duotone: A two color halftone reproduction from a one-color photograph.
Duplicating Film: Special films made for color and black and
white uses.