Packet: A networking transmission unit of fixed maximum size that consists of binary information representing both data, addressing information and error-correction information, created by the data-link layer.
Packing: In lithography, the paper used to underlay a blanket, plate or proof to bring the surface to the desired height, the method of adjusting squeeze pressure. The act of inserting the packing material under the blanket or plate.
|A3||11.69 x 16.54||297 x 420|
|A4||8.25 x 11.75||210 x 297|
|A5||5.83 x 8.25||148 x 210|
|B5||6.93 x 9.84||176 x 250|
|Executive (Monarch)||7.25 x 10.5||184 x 267|
|Legal||8.5 x 14||216 x 356|
|Letter||8.5 x 11||216 x 279|
|Magazine - Broad||10 x 12||254 x 305|
|Magazine - Narrow||8.125 x 10.875||206 x 276|
|Magazine - Standard||8.375 x 10.875||213 x 276|
|Magazine - Wide||9 x 10.875||229 x 276|
|Periodical||10.25 x 13||260 x 330|
|Tabloid||11 x 17||279 x 432|
See also standard Envelope Formats.
Page Make Up: In stripping, the assembly of all elements to make up a page. In electronic scanning, the assembly of page elements such as type, logos, and color separations in position to compose a complete page with all elements which are then displayed on a video terminal as they will appear in the final reproduction.
Pagination: The assignment of page numbers, either manually or electronically, in a document.
Paint Brush: A function in the toolbox of painting, drawing, and image manipulation programs. By moving the cursor on the video monitor, brush strokes of varying size and shape can be generated electronically and displayed on the screen.
Pair-kerning: Automatically kerning selected pairs of characters when they would otherwise be spaced too close or far apart. Characters that are pair-kerned are specified by the font designer.
Palette: The collection of colors, shades, or patterns that can be selected and displayed on a video screen with the aid of a computer and a graphics program.
PANTONE Colors: A color system of over 1200 standard colors developed by Pantone, Inc., Moonachie, NJ (201)935-5500.
Paragraph Alignment: An electronic function for positioning of text within a box or column; alignment can be left, right, centered or justified.
Parallel Interface: An interface between a computer and a printer in which the computer sends multiple bits of information to the printer simultaneously. Parallel and Centronics interfaces are the same type.
Parallel Transmission: Sending dtat from a computer down several wires simultaneously, the pulses in one wire being precisely synchronized with the pulses in the other wires.
Parity: Used in error correction. A separate bit _ the parity bit _ is added and manipulated so that the number of 1s is odd (for odd parity) or even (for even parity). If the number of bits sent don't conform to the parity, the software detects and error.
Partition: A partition is a portion of a physical disk that functions as it were a physically seperate unit.
Partition Table: The partition table contains entries showing the start and end point of each of the primary partitions on the disk. The partition table can hold 4 entries.
Paste: To transfer the contents of the clipboard () to an application. Many applications have a Paste Command that performs this task.
Pattern Matching: A computerized search operation whereby input values are treated as patterns and matches are sought in a search database. Whenever exact matches occur, this is called a hit, the results of a search produce a list of hits for further investigation.
PC: Short for IBM Personal Computer. Used to indicate an IBM or compatible. sometimes used more generally to indicate any personal computer.
PCI: See Peripheral Component Interconnect.
PDL: Page Description Language.
Peaking: A common expression used to describe the electronic manipulation of gray tones to increase contrast in an image.
Peripherals: A connectable device that has an auxiliary function outside the permanent system configuration.
Perl: An interpreted programming launguage developed by Larry Wall, Perl offers superb string-handling and pattern-matching capabilities and is a favorite among CGI programmers.
Phosphor: Substance which glows when struck by electrons. The back of a cathode ray tube face is coated with phosphor.
Photochromic: Compounds that become dark when exposed to light, and can be made clear again by removing the light, or exposing them to light of another wavelength. Proposed as erasable optical storage media.
Photocomposition: The manipulation and transfer of graphic images and text, using photographic means, to a light-sensitive paper or film.
Photomechanical: This term is used to describe stripping flats which are to be exposed on a printing plate. It can include line negs, film positives, halftones and color separations.
Photomultiplier (PM): A photo cathode having extremely high stability and capable of reading low level light measurements in the entire part of the visible spectrum (as well as some non-visible radiation). PM's are capable of reacting to extremely short duration exposures of light as well as continuously changing conditions of light values. These PM's can read, disseminate, boost up signal and pass the information along (in microseconds) to the color computer where these signals are adjusted to conform and create the necessary color balance and depth of color to make the final separation. The photomultiplier is located in a group of four in the scanners head and measures the light transmitted through or reflected from the original copy and through corresponding color filters to create the color printers.
Photoshop: A Macintosh-based software program created by Adobe Systems, Inc. for the manipulation of scanned images for PostScript output.
Phototypesetter: Device that uses photographic techniques to reproduce machine-readable text on light-sensitive paper and film.
Pi characters: Special non-text characters, such as mathematical symbols.
Pica: Unit of measurement used in typography and graphic design. Approximately 1/6 inch.
PICT: A picture file format developed by Apple Computer, Inc. for use on Macintosh computers. The PICT format is adequate for storing and displaying data at 72 dpi, using the Macintosh screen, but is not sophisticated enough for higher-quality work.
PIF: Program Information File. A file that provides information that Windows needs to run a non-Windows application.
Pin Register: The use of accurately positioned holes and special pins used on copy, film, plates and printing presses to insure proper registration and to assure the fit of all elements.
Pixel: An acronym for Picture Element. when an image is defined by many tiny dots, those dots are pixels. A pixel represents the smallest graphic unit of measurement on a screen. The actual size of a pixel is screen-dependent, and varies according to the size of the screen and the resolution being used.
Pixilate: The electronic function by which pixel size can be increased to enable easy manipulation in creating special effects.
Plot: To use vector graphics: that is, to draw images with many straight lines, rather than dots.
Plotter: A printer that prints vector graphics, i.e., images created by a series of many straight lines.
PMS: Pantone Matching System. A means of describing colors by assigning them numbers. See also Pantone Colors.
Point: Unit of measurement in typography, approximately 1/72 inch. There are 12 points in a pica.
Point to Point Protocol (PPP): The industry standard that is implemented in dial-up networking. PPP is a line protocol used to connect to remote networking services, including Interet Service Providers. Prior to the introduction of PPP, another line protocal, SLIP, was used.
Polaroid Prints: Instant prints, self developing, which are unsuitable for color reproduction.
Poor Trapping: In printing, the condition in wet printing lithography when less ink transfers to a previously printed ink than to unprinted paper. The general problem is usually unsuitable ink tack, but can also be affected by the surface of the paper, the pH of the water and alcohol, improper blanket packing, oversensitive plates, ink of poor quality, incorrect ink sequence, etc.
Port: A socket, usually at the back of a computer, allowing the computer to be connected to other devices.
Portrait: A page whose width is shorter than its height.
Positive: In photography and lithography, a film or print containing an image in which the light and dark values are the same as the original. The reverse would be a negative.
PostScript: A page definition language (PDL) developed by Adobe Systems. When a page of text and/or graphics is saved as a PostScript file, the page is stored as a set of instructions specifing the measurements, typefaces, and graphic shapes that make up the page.
PPD File: PostScript Printer Description file. A file that contains information on screen angle, resolution, page size and device-specific information for a file to be printed on a PostScript device.
Prepress: The preparation work required to turn "camera-ready" artwork into the printing plates needed for mass production, i.e., making negatives, "stripping" or placing the negatives in place, and etching the plates.
Press Proofs: In color reproduction, a proof of a color subject on a printing press, using the same color inks and paper stocks on which the final run will be done on. This proof is done prior to the final reproduction and is the only true and predictable way to show proof of what is contained in the litho films. There is no other proof system that takes into account printing aspects such as absorbency of stock, hue of inks, trap and other printing mechanics which occur on a press.
Primary Colors: Additive primaries are red, blue and green. The subtractive primaries are cyan, magenta and yellow. (see additive and subtractive primaries.)
Print Engine: Inside a laser printer, the mechanism that uses a laser to create an electrostatic image of a page and transfers it onto a sheet of paper.
Print Quality: In paper, the properties of the paper that affect its appearance and the quality of the reproduction.
Print Queue: A list of files that have been sent to a particular printer. The list includes the file currently printing and those waiting to be printed.
Printing Dot: The smallest graphic element, and the particulate base for all graphic elements when reproduced in print.
Process Colors: In printing, the subtractive primary process ink colors are cyan, magenta, yellow plus black in four color process printing.
Process Color Printing: The recreation of color by combing two or more of the subtractive colors _ cyan, magenta, and yellow, plus black.
Process Lens: A highly corrected photographic lens for the graphic arts used to record linework, halftones or color separations when using the direct screen method.
Process Printing: The printing from a series of two or more plates containing halftones representing process colors in order to produce intermediate colors, shades and tones.
Progressive Proofs (Progs): Proofs made from separate plates in process work, usually during a press proof, showing the sequence of printing and the result after each additional color has been applied. Can be used most effectively to determine if any problems exist and can be used on a basis for corrections or future reprinting. There are six two-color combinations plus the four process colors (c&m/c&y/c&k/m&y/m&k/y&k) and there are three (k&c&m/k&y&m/k&c&y) three color combinations.
Proof: In graphic arts, a colored material, substrate or dye used to simulate the subtractive printing primaries of cyan, magenta and yellow and also includes black as well as the other colors. The colorants used in these proof materials should render process colors with no apparent hue error. When the proof colors are combined in registration they will show the approximate printing values, colors and hues of how an original will look when printed or compared to how the original looked.
Proportional Leading: A method of leading in which two-thirds of the leading space is above the text baseline and one-third of the leading space is below the spaceline.
Protocol: A set of rules that define how computers communicate with each other. Protocols are used between instances of a particular layer on each computer. Windows 95 includes NetBEUI, TCP/IP, and IPX/SPX-compatible protocols.
Psychological Aspects of Color: The sensations of color are hue, saturation and brightness. None of these is directly measurable by the human eye. The eye cannot distinguish component wavelengths in a single color. When two lights of different colors are mixed to produce a third color, no human eye can detect its composite nature. The simple fact is that the sensation of color to one observer can vary and be different to another observer. And in the printing process, the eye cannot measure ink film thickness. That is why densitometers are used to measure ink density.
Pull-Quote: Style of taking a short phrase in the text and repeating it in larger text.
Push, Pull: In photography, the deliberate manipulation of the film speed in order to achieve exposure and operative controls beyond the normal range and limitations of the film. By pushing (over development) the effective speed (ASA) can be increase. By pulling (under development) the effective speed (ASA) of the film can be reduced. Note: pushing and pulling film create undesirable results such as grain, contrast and color shifts.
Push Installation: A method of installing software automatically accross a network.