16 Bit: Information coded in 16 bit (2 byte) can take 216 = 65536 different values (0 to 65535); in 16-bitgreyscale each pixel can show 65536 shades of grey.

24 Bit RGB: In 24-bit-RGB 8 bits are assigned to each of the components red, green and blue of the pixel. The colour of each pixel can be coded on 16.7 million (or simply “millions of”) different levels.

32 Bit CMYK: In 32-bit-CMYK, 8 bits are assigned to each of the components Cyan, Magenta, Yellow and Black of the pixel. The colour of each pixel can be coded on 4.3 billion different levels (which does not mean 4.3 billion different colours can be shown); indeed black is not a primary colour.

4-Colour: A printing process that uses black (K) in addition to the primary colours (CMY).

6-Colour: A printing process that uses black (K), light cyan (Lc) and light magenta (Lm) in addition to the primary colours (CMY).

8 Bit: Information coded in 8 bit (1 byte) can take 28 = 256 different values (0 to 255); in 8-bit-colour each pixel can show 256 colours or shades of grey.

Additive Color: A color model associated with the RGB (red, green, blue) method of representing color. Equal amounts of the primaries will combine to produce the perception of white light. This is normally used in video systems/monitors.

Adobe Illustrator™: A software package for designing and illustrating. Some features include: a complete set of drawing tools, on-screen drawing and EPS-file formatting.

Airbrush Printer: A large, digital-print machine (for printing billboards, etc.) that uses compressed air to drive inks through the printhead.

Aliasing: The stair-stepped pattern in a bitmap image when the resolution is too low for the size of the output; also called “jaggies”.

Anti-Aliasing: A technique that smoothes the printed appearance of stair-stepped (jagged) lines. One method is to fill the edges of the line with varying shades of color (or gray). This method averages the brightness values of the edges.

Anti-Graffiti: Laminate with a hard smooth surface to facilitate removal of paints and marker inks.

Application: A computer software program that performs specific functions such as page layout, word processing, accounting, drawing and spreadsheet formation.

Aqueous Inks: Water based inks; inks that use water as carrier for the dyes or pigments as colorants.

ASCII (American Standard Code For Information Interchange) (Pronounced As-Kee): ASCII is a computer code used to transfer numbers and text data between computers that run different software applications.

Aspect Ratio: The relation of height to width of a picture.

ATM®: Adobe® Type Manager® software, which makes type appear sharp and clear on-screen and in print.

Back-lit: Semi-translucent polyester film, coated for inkjet printing, for use in light boxes.

Banding: In digital printing, this term refers to patterns on a print caused by insufficient color or gray-scale ranges within the output device's image processor, or insufficient information contained within the original scan.Banding is most noticeable in printed areas that fade from light to dark.

Binder: Non-volatile ingredient of an ink; it binds the pigments together to form the ink film and bonds that film to the media to which it is applied.

Bitmap: Generally, a bitmap is associated with graphics objects. The bits are a direct representation of the picture image. In a monochrome system, one bit in the bitmap represents one pixel on screen. With color (or gray-scale) systems, several bitmaps in the bitmap represent one pixel or group of pixels.

Bleed: Printed area which extends off the trimmed area. It is not possible to print all the way to the edge of the paper sheet. To achieve this effect it is necessary to print a larger area than is required and then trim the paper down. Typically a designer would allow an extra 3mm of bleed to colour and image areas to allow for a little leeway when trimming.

Block-Out: Banner substrate or self-adhesive film that is totally opaque and does not let any light pass.

Blooming: Overexposure in digital devices; results in loss of detail and distortion at colour boundaries.

Brightness: Lightness value of a pixel ranging from 0 (black) to 255 (white). Also the light reflectivity of a printing media; different brightness levels change the appearance of colours and thus require adjustments in calibration.

Bubble Jet: Thermal inkjet printing systems associated with low cost desktop printers. The term is also used by Canon to describe thermal inkjet.

Calibration: Optimising settings for a printer/ink/media combination to known specifications in order to achieve accurate and consistent reproduction of the final print.

Channel letters: A fabricated dimensional letter without a back.

CIE (Commission Internationale de l' Eclairage): An international color standards group sometimes known as the Intl. Committee on Illumination. In 1931, using a spectrophotometer to precisely measure color, this group defined a color model where numbers describe colors along three axes. Because this system can be used to store color information, it has become a crucial part of device-independent, digital-print systems. There are newer color models in addition to the CIE.

CIE: Commission International de l’Eclairage, an international organisation that developed colour definition standards, endorsed by Adobe Systems.

CLUT (Color Look-Up Table): Another term for a correction table, a CLUT is a color-management software reference file that maintains the proper calibration of devices, such as monitors, printers and scanners. (See also, LUT.)

CMYK: The four process colors -- cyan, magenta, yellow and black -- mixed to provide a color image; typically used in printing applications.

Coatings: A clear coating provides protection from smudging, fingerprints, and water droplets. It does not improve the permanence of the print because most fading is due to visible light. On some material, such as canvas, coating can render a print water-resistant, allowing it to be framed without glass.

Cold Lamination: Application of a clear self-adhesive film (PVC or polyester) to protect a print or other substrate; may contain UV-filters; uses pressure sensitive adhesives. Cold lamination is appropriate when heat would adversely affect the substrate.

Color Correctness: The depth and accuracy of an image's color representation, typically influenced by the color depth and palette of an image.

Color Depth: The amount of color information in an image, reflected in the # of color bits compression, lossless scheme of organizing information in a more compact form where all of the original information is retained, while gaining a moderate level of compaction scheme of organizing information in a more compact form.

Color Gamut: The tonal range of colors that can be reproduced by a digital device.

Color Management System (CMS): Software that allows applications and printer drivers to access information about the color characteristics of monitors, printers, and scanners. The Color Management System uses the color information to provide accurate and consistent color to the output device.

Color profile: Also called device profile. This term refers to the relationship between the color models of the system devices.

Colorants: Substances such as dyes and pigments that make up colours in inks.

Color Sync: System extensions (CMS) developed by Apple Computer that manage the colour description of different devices working together.

Colour Separation: Process of creating separate patterns of films for each colour component (one for each of cyan, yellow, magenta and black) for printing.

Compression: The process of removing irrelevant information and reducing unneeded space from a file in order to make the file smaller.

Continuous Tone: Like original photographs, drawings or paintings, continuous-tone ../image contain real gradients of grays or colors.

Contour Cutting: Cutting around outlines of a printed image on a self-adhesive media with a printer capable of “print-and-cut”.

Contrast: A measure of the ratio of brightness between the lightest and the darkest areas in an image.

Cropping: A process whereby a portion of an image is removed, usually from the outside of the image, to eliminate unwanted areas.

Curl: Bending that occurs spontaneously at the edges of a media when laid on a flat surface; may be caused by atmospheric humidity or by oversaturation with ink.

Cutting Plotter: A vector-driven device (similar to CAS plotters) for cutting sign-making substrates. Recent designs include digital-print (inkjet) systems combined with cutting-plotter systems. (See also, Plotter and Printer/cutter.)

Cyan: The “blue” colour in 4-colour CMYK printing; commonly know as process cyan.

Densitometer: Device used to measure the percentage rate of light that is reflected or transmitted by the surface of a substrate thus indicating the absorption rate.

DIB: Device Independent Bitmap, a variant of a bitmap (bmp) file consisting of header field, an optional pallette, and bitmap data; bitmap has an additional header field.

DIC (Device-Independent Color): The goal of DIC is to provide an independent, universal standard against which color spaces of all devices in a system can be referenced.

Die-Cutting: The use of a sharp, formed piece of metal to cut out contours in a substrate, for example in selfadhesive vinyl to make stickers.

Di-Electric Media: Specially treated substrates that hold an electric charge for printing on an electrostatic printer.

Digital Color Printing: To use multiple printheads that place specified colors of inks in predetermined places. The results are similar to photographs, but are often larger. In fact, some are billboard size.

Digital Fine Art Print: A fine art print made by any digital process.

Digital Imaging / Digital Printing: Digital imaging refers to the routines that take place before the output methods occur. These routines include: scanning, photo manipulation, color correction and RIPing. Digital printing, on the other hand, refers to a variety of computer-controlled output methods: inkjet, computer-airbrush, thermal-transfer and electrostatic printers and copiers.

Digital Printer: Any printer capable of transforming digital data files into material copies. The most common printing technologies are thermal inkjet, piezoelectric inkjet, thermal transfer, electrostatic, offset and laser.

Digital Signature: A pattern in a digital print that shows the breakdown of an image into individual segments, such as pixels.

Dimensional Stability: The ability of vinyl or paper to retain its original dimensions under stress or changes in moisture or temperature.

Dimensional: Letters with depth.

Direct Digital Printing: Commercial-quality printing in which electronic source files are processed directly on the printing press or printing system, rather than through analog steps such as film ../imageetting and platemaking. Direct digital printing systems may be based on lithographic offset technology or laser/toner technology. Front-end RIPs and servers are integrated components of these printing systems.

Dithering: Method for simulating shades of grey of colour by only limited number and by varying size and shape of pixels.

Dmax: Highest density one can reach for a substrate on a printing system (printer and ink). Values higher than Dmax do not show on the image.

Dmin: Lowest density one can reach for a substrate on a printing system (printer and ink), normally white. Values lower than Dmin do not show on the image.

Dot Gain: A term that refers to the "weight gain" of halftone dots. During the printing process, the half-tone dots increase in size. Because this is an inherent part of the printing process, the effect of increased dot size should be anticipated ahead of time.

Dot: Smallest single ink mark or spot on the printing substrate.

DPI (Dots Per Inch): A measurement of linear resolution for a printer or scanner. For example, a resolution of 300 dpi means that there are 300 dots across and 300 dots down. A higher number of dots creates a finer resolution.

Drying Time: Time required for a print to become touch dry.

Dye Inks: Organic colorants in inks; dyes have the ability to completely dissolve in a liquid (as opposed to pigments which a); dyes are brighter and have a higher saturation but are less stable over time; mainly used for indore insolubleor applications.

Dye Sublimation: Colour printing technology in which the ../image are printed in reverse on a carrier and then transferred to the final substrate; heat or pressure activated.

Eco-Solvent Inks: Inks that contain weaker and less solvents than pure solvent inks. In addition, they are cheaper but not necessarily more environment-friendly than pure solvent inks. Mutoh says their Eco-Solvent Plus ink is a solvent-based ink, not containing any dangerous solvents nor spreading any VOCs (volatile organic compounds) into the environment. Roland makes a similar claim for their Sol Ink. Eco-solvent inks use slow-drying liquids as the carrier fluid. Therefore, printers that use these inks often have heaters fitted to aid with ink drying.

Electrostatic Printing: Printing large-format prints in a process similar to, but not the same as, color photocopiers. If properly done, (and laminated) the ../image are used for billboards, truck graphics, banners, signs or murals.

Encapsulated PostScript (EPS): A standard file format for importing and exporting PostScript® language files among applications in a variety of heterogeneous environments.

Error Diffusion: In actuality, error diffusion is a random dot-placement strategy (or dithering method), spreading out the inherent failing until it is indistinguishable to the naked eye.

Etching: A method for carving into the surface of a material, particularly metal.

Fading: Reduction of colour density over time mostly due to exposure to UV rays, environmental pollutants and abrasion by dust. Magenta and yellow fade faster than black, which is very stable. Lamination with a UV filter will considerably slow down the process.

Feathering: The spreading of ink into a non-printed area due to the capillary action of the fibres of the substrate causing blurred ../image.

Filler: Material added to an ink to increase opacity; cheaper than pigment. Normally this is chalk or clay.

Floor Graphics: Digital image applied on floors protected by a tough grained laminate.

FM (Frequency-Modulated) Screening: A dithering method that uses uniform dot sizes and varies the distance between them. This method is different from conventional halftone screening, which aligns dots of varying sizes on a regular grid.

Foil: Wax-based or resin-based colour ribbon for thermal-transfer printing; the thin plastic film travels over heated print head and is placed on a substrate by a combination of heat and pressure from the print head.

Fonts: Typefaces in different styles that give documents personality.

Food Grade: Inks that comply with laws and regulations for use on food packaging or marking of food products.

Foot: Unit of length, 12 inches; 1ft = 30.48cm.

Four Colour Process Printing: The most common system for producing full colour print. Originally the artwork and originals were separated using filters and four printing plates were produced. The four ink colours are Cyan (Blue), Magenta (Red),Yellow and Black - often referred to as CMYK. Because the inks used are translucent, they can be overprinted and combined in a variety of different proportions to produce a wide range of colours. The vast majority of magazines and colour books are produced using four-colour process.

Full Bleed: Printed picture or background that extends to the final trim edge of the media.

Future Ink Test Print: From time to time, new inks are released to the marketplace that offer improved longevity, a larger color space, or both. A printer may switch production to new inks if the improvements are material and have been certified by an independent laboratory. Prints from files that were made with older inks will look different when printed with new inks. The future ink test print provides an opportunity to evaluate the effect of using new inks on the print.

GA Ink: Dye ink with wide colour gamut for graphic art applications made by Encad.

Gamma: Measure of the extent of how compressed or expanded the dark and light shades become in an image.

Gamut: The range of colours that can be reproduced by a printer

GCR: Grey Component Replacement; colour separating process that replaces the black obtained through portions of cyan, magenta and yellow by true black; this achieves more economical ink consumption and avoids the risk of ink quantities not being absorbed by the substrate. in addition this allows to obtain a better neutralisation of the grey tones and achieve a higher Dmax.

Giclée (Fr. "A Spraying of Ink"): A common term for fine art digital prints, especially those done on Iris or Roland printers.

GIF: Graphics Interchange Format, a lossy compression technique, popular for exchanging files electronically, especially on Compuserve; all files have a corresponding palette; maximum colors = 256.

Gloss: Property of a smooth surface with a shiny appearance; different gloss levels are measured as the percentage of light refracted from a surface at certain angle.

Go Ink: Pigmented outdoor ink with high durability and UV-resistance made by Encad

Gradation: The transition between colors or shades. Gradation occurs by mixing percentages of dominant and secondary color and then altering those colors to bring about a change.

Grand Format: Super-large digital-print machines. Their printing process is usually driven by air, but recent machines may piezo print directly on a substrate.

Graphical Display Interface (GDI): The display language interface for Microsoft Windows systems. GDI printers are compatible only with Windows systems and do not offer the performance and features available with Adobe PostScript or Adobe PrintGear® printers.

Grey Balance: Amount of cyan, magenta and yellow required to obtain a neutral grey.

Greyscale: Range of neutral colours; at 8 bit a file can have 256 levels of grey (including black and white).

GSM: Abbreviation for grams per square metre. This indicates the weight of paper or other stock. For example; A typical photocopier paper would be 80 gsm - a good letterhead paper might be 100 gsm - a postcard would be about 250 gsm.

GX Ink: Archival dye ink with high UV-resistance made by Encad.

Halftone: The method of producing a range of tones, such as a photograph or tinted area, by dividing the image into a series of dots. Dark areas have relatively big dots, close together. Light areas have small dots surrounded by white space. The number of dots used determines the quality of the image produced. In a newspaper the halftone dots are easily visible to the naked eye - the screen used can often be as coarse as 60 dpi (dots per inch). A colour magazine would typically use a screen of 150 dpi - An art book, 175 dpi or finer. A halftone screen can be applied to a solid colour in order to produce tints of that colour.

Halo: Lightening of black ink when it is printed near another colour.

Head Crash: Accidental contact of an inkjet nozzle or the complete head with a substrate during printing.

Hexachrome: A colour matching system that allows the combination of 6 colours (CMYK, orange and green) in order to reproduce a larger gamut of colours; developed by Pantone Inc.

Hi-Fi Jet: Range of piezo inkjet printers made by Roland DG.

Hi-Fi: 6-colour printing used to obtain a more subtle rendition of light tones beyond that of traditional 4-colour processes by adding light cyan and light magenta.

High Resolution Scan: Professional scan at an output resolution of 150 dpi or 300 dpi using color optimized for archival inks on fine art media.

High Resolution: The reproduction of ../image with a great amount of detail or a high level of gray scaling, adding greater detail and sharpness to halftones.

Hot Lamination: Application of a clear layer to protect a print or other substrate; may contain UV-filters; uses heat to activate the adhesive and thus cannot be used on heat sensitive substrates. Prints must be completely dry before lamination to avoid bubbles due to trapped moisture.

HSV: Hue, Saturation and Value; a colour model in which colour is described in terms of chromatic colour, its intensity and its variation from light to dark.

Hue: One of the components of colour represented by angle of a 360° colour wheel.

Humectant: Soluble component of inkjet inks that is used to preserve the moisture content of the inks.

IAFADP: International Association of Fine Art Digital Printmakers, the trade association of leading digital printing studios.

ICC Profile: Colour profile conforming to ICC specifications.

Image Letters Typesetters: Devices that generate the highest resolution paper, plate, and film output for professional publishing needs.

Imposition: The process of arranging individual pages on a form in preparation for the printing press so that the pages will be in proper sequence after printing, folding, and binding.

Ink: Ink is composed of a carrier (water or solvent), colorants (pigments or dyes) and a binder (to fix the inks); may also contain alcohols.

Inkjet printer: A type of printer that sprays tiny streams of quick-drying ink onto the paper. An inkjet printer produces high-quality printing like that of a laser printer.

Inkjet, Bubblejet: Specifically, Bubblejet is a tradename for a Canon desktop inkjet printer. Bubblejet is also a name used to describe "thermal"-type inkjets.

Inkjet, Phase Change: This type of inkjet technology uses solid wax inserts instead of traditional inks. The wax is melted and deposited onto the substrate through the printhead.

Inkjet: Printing process where ink is projected as dots onto a substrate in a pattern to form an image. The most common technologies are thermal inkjet that heats ink in the printhead to the boiling point and piezo-electric inkjet that applies an electric charge to a piezo-crystal which in turn changes its shape and thus expels the ink through the nozzles.

Intensity: Degree of saturation or reflection of light.

Interface: The ways a printer may be connected to a computer or network. Adobe PostScript printers support a wide variety of interfaces, including serial, parallel, AppleTalk, and Ethernet.

International Color Consortium (ICC): A group of companies chartered to develop, use, and promote cross-platform standards so that applications and devices can exchange color data without ambiguity. Founding members include Adobe, Agfa, Apple, FOGRA, Kodak, Microsoft, Silicon Graphics, Sun, and Taligent.

Interpolation: Process used to artificially increase or decrease the number of pixels of an image, thus improving apparent resolution.

Interpreter: The Adobe PostScript Raster Image Processor (RIP) that translates the instructions in a PostScript language file sent from the printer driver.

Iris Papers: Papers distributed by Iris Graphics for use on their inkjet printers. These include glossy, semi-matte and matte papers, which are used for commercial proofing. Also available are some fine art papers such as Arches for Iris, a paper manufactured by Arches specifically for use on Iris printers.

Iris Print: A print created on an Iris inkjet printer. Also called Iris giclée.

JPEG: Joint Photographers Expert Group; a compressed, lossy format which is symmetrical, i.e. takes the same amount of time to compress as decompress; maximum colors = 16.7 million.

Justify: To space a line out uniformly to the correct line length of the page.

L*a*b*: Colour based on values of light (L), red-green (a) and yellow-blue (b).

Laminate: Thin clear (transparent) plastic film applied to a media (vinyl, paper etc.) providing protection against humidity, abrasion and other wear; also enhances existing colour, providing a gloss, satin or matt surface appearance.

Lamination: A plastic coating which protects the printed surface and usually gives a high gloss finish. Most paperback books have laminated covers.

Large Format Printing: Printing on sheets larger than A3 or on rolls from 36in (914mm) wide.

Large Format: Large format generally refers to a manufacturer's definition of its product.

Layouts: Documents describing the precise layout of a print or prints on a sheet of paper. The layout indicates both the exact size of the prints and the amount of white space around each print.

Levels of Grey: Number of shades of grey between white and black.

Light Magenta/Light Cyan: Modified forms of the corresponding primary colours; help to achieve a more subtle rendition of light tones and more natural looking continuous tone prints on 6 colour printers.

Line Artwork: Artwork which contains no halftones such as company symbols or simple diagrams.

Line Illustration: A black and white drawing containing no gray or midtones to be used for reproduction.

Liquid Laminate: Clear coat applied to a printed surface as a protection against humidity and environmental aggression; can be applied with a brush, as a spray or in a laminator.

Location Map (Spotted Map): A map annotated with all the locations included as part of a specific out of home media program.

Low Resolution Graphics: The reproduction of ../image with a minimum amount of detail, resulting in a jagged-looking object when output.

LPI (Lines Per Inch): A traditional halftone screen measurement that refers to the number of lines of dots per inch.

Luminance: The brightness of an image.

Luminosity: Brightness of a single colour.

LUT (Look-UpTable): The storage space for pre-set measurements and adjustments for different media, file types, printers, etc.

Magenta: The purple-red colour in 4-colour CMYK printing; commonly called process magenta.

Margins: The unprinted area between the text body and front, gutter, top, and bottom trim.

Media: Another term for substrate. The materials to be printed on, such as watercolor papers, canvas, copper, wood veneer, cotton, plastic and exotic papers like Japanese Kochi.

Megapixels: Maximum total number of pixels of a device; calculated by multiplying the number of pixels per row with the number of rows.

Metre: Basic unit of length; 1m = 3.28ft.

Micron (UM): One thousandth of a millimetre (100μm = 3.9mil).

Mil: One thousandth of an inch (1mil = 25μm).

Millilitre: Liquid volume equivalent to one thousandth of a litre (1ml = 0.03381 fluid ounces).

Millimetre: One thousandth of a metre (1mm = 0.039 inch).

Mirror Image: Reversing an image to be looked at through a clear or backlit film, or for transfer prints that are applied backwards (on the side of the light source) onto the substrate.

Moire: When a photograph has already been screened once (usually a picture that has been printed before) and is screened again, conflict between the previous screen and new one occur, causing an undesirable pattern.

Monochrome: One colour; commonly refers to printing in black on white.

Nozzle: Tiny hole in the orifice plate of the print head from which the ink is expelled.

Opacity: Percentage of resistance of light passing through a substrate; measurement for the capacity of underlying colours or ../image to show through a media.

Opaque: Light blocking substrate; one side does not show through to the other.

Open Prepress Interface (OPI): A set of PostScript language comments for defining and specifying the placement of ../image on an electronic page layout.

Optical Resolution: The maximum actual (true) resolution of a scanner without interpolation.

Original Digital Print: Artwork that is created entirely or largely on the computer, often by scanning in individual elements and then combining them electronically.

Originals: The basic elements of the artwork. Includes photographs on print or transparency, illustrations, line artwork etc.

Overlaminate: A protective clear film that extends an image's outdoor life and enhances its visual quality.

Page-Description Language (PDL): Software that resides within a printer and defines how elements such as text and graphics appear on the printed page. PostScript is the industry-standard page-description language.

Pages Per Minute (PPM): The maximum speed of the printer's marking engine as rated by the manufacturer.

Panel: Also called a tile. A division of a job based on a device's production area.

Pantone: The brand name of a colour matching system produced by Pantone, Inc of the USA. A large range of inks are specified and identified by number to produce standard results across the industry. A reference such as PAN199 indicates a colour in the Pantone range, in this case a bright red. In a colour swatch book the number PAN199C would indicate how the colour looks when printed on Coated or glossy stock. PAN199U indicates how the same ink appears when printed on Uncoated or matt stock. Sometimes the difference can be quite dramatic. It is worth remembering that Pantone inks provide a much greater range of colours than can be achieved using CMYK. This is important if trying to match work printed in four colour process with that printed in special colours.

Pass: Travel of a print head assembly over a substrate; one-pass printers use an assembly of several head to deposit all colours in one run; multi-pass printers require a separate run for each colour.

PDF: Portable Document Format; graphic file format that allows distribution of unalterable documents with the original formatting including pictures and fonts across platforms; developed by Adobe Systems Inc.

Perforation: Sequence of holes, evenly spaced or in regular patterns, along the edge of a media for use on sprocket fed printers.

Permanent Adhesive: Adhesive that creates a permanent bond between a printing media and a substrate; difficult to remove after application without leaving adhesive residue on the substrate.

Photo CD: A Kodak process for scanning transparencies (slides) and storing them on CD in a format known as Photo CD. Acceptable results can be achieved from Photo CD's, but the professional version is required to create large enough files.

Pica: A compositor’s unit of measure approximating one-sixth of an inch or 12 points.

Piezo/Micropiezo: A printer head technology that uses micro-electric firing of crystals to control the flow of ink to the substrate.

Permanent: An outdoor display that remains at a specific location for an extended period of time, usually for a one year term.

Piezo-Electric: Printing technology that uses an electric charge on a piezo-electric crystal to control the flow of ink droplets through the nozzle. The piezo crystal expands and contracts and each time expels an ink droplet. Since the ink does not need to be boiled, as is the case on thermal heads, the piezo printers are more reliable. Also since there are no heating elements the print heads themselves need to be replaced less often. Epson, Mimaki, Mutoh and Roland manufacture piezo printers.

Pigment Inks: Colorants in inks; pigment particles in the liquid medium form a suspension and do not dissolve in a liquid (as opposed to dyes); pigments are more stable over time. Pigments are often based on naturally occurring (inorganic) minerals such as metal oxides or charcoal.

Pinholes: Tiny round spots that are not covered by ink

Pixel: Picture element, or the smallest unit of the computer screen. A pixel can be monochrome or up to the pixel depth available on your color system. Pixels are also used for identifying screen resolution, e.g. 72 pixels per inch.

Pixelisation: Effect that occurs when pixels of an image are enlarged to increase the picture size with a lower PPI; may result in aliasing.

Pixels Per Inch (PPI): Sometimes termed dots per inch, this represents resolution

Plotter: A term that refers to the CAD origins of wide-format printers. A printer, so to speak, that graphs computer output.

PMS: Pantone Matching System, an industry standard color ink system, frequently used for matching colors across materials.

Point: A compositor’s unit of measurement to designate size of type.

PostScript®: An Adobe programming language that enables text and graphic ../image to be output from different devices with consistent and predictable results.

PPI (Pixels Per Iinch): A measurement of resolution. A pixel is a unit of data that should not be confused with dpi (dots per inch) or lpi (lines per inch). If there are more pixels per inch, the image will be sharper.

Pre-Press: All processes performed on a printing order before it goes to the press to be printed: copy writing, page layout, scanning, artwork, colour proofing etc.

Primary Colors: Set of basic colours that make up other colours; additives colours are red, green and blue, together they make up white light; subtractive colours are cyan, magenta and yellow, together they make up black; real black is often added in printing to obtain a richer black.

Print File: The file used to produce a final proof that is archived for producing current and future printings of an edition.

Print Head: Component on inkjet printers that forms the ink droplets and drives them onto the substrate; comprises inkfeed, transducer (thermal or piezo) and nozzle. A printer can have 64 or 128 nozzles that can expel ink simultaneously. The major print head manufacturers are Brother, Epson, Spectra and Xaar.

Print on Demand: The digital process enables the reproduction of prints over a long period of time with consistency, allowing orders of small numbers of prints whenever needed. While the process offers a high degree of consistency, editions that require exact matching should be printed at one time.

Print Quality: The characteristics of a printing sub-system, such as the number of lines per inch and paper quality, which influence the perceived quality of a printed image.

Print Spooler: Holding area such as memory space or hard disk space where data files wait before they are sent to a printer.

Print Zone: Area of a media that the printer is capable of printing on leaving unprinted blanks along the edge.

Printer Driver: Software that serves as the communication link between applications and the page-description language used by printers.

Printer-Cutter: Inkjet printer that also cuts contours. Roland and Summagraphics manufacture printer-cutters.

Printmaker: The person who does the actual printing of a digital image. A printmaker uses a printer (the equipment) to make a digital print.

Process Colors: Ink colours that combine and thus can reproduce any other colour; normally cyan, magenta and yellow; black is often added to save consumption of the basic colours.

Profile: Settings of a colour management system that contain the colour reproduction characteristics of each device (scanner, printer etc).

Proprietary: Materials or software designed for use with one specific machine.

PVC: Polyvinyl Chloride commonly called vinyl; soft thin plasticised film, mostly white or clear in a variety of surface finishes (gloss, satin, lustre, matt). For printing applications normally self-adhesive; available coated or uncoated; clear versions also used as laminates.

Raster: Image made up of individual pixels.

Reflective: Ability of a surface to effectively bounce back most or all of the wavelengths of incoming light.

Removable Adhesive: Low tack adhesive that does not create a permanent bond between a printing media and a substrate; remains easy to remove for a defined duration after application and does not leave any adhesive residue on the substrate.

Render: The actual and final display of an image or print after transmission or transformation.

Repellency: Ink does not adhere evenly to the media and tends to pearl off; may be due to improper handling of the media (fingerprints) or when inks do not match the printing surface; often occurs on substrates with a high gloss finish.

Resampling: Changing the resolution of a picture file without changing its size.

Resize: It is generally possible to resize files so prints can be made either smaller or larger. Significant upsizing is usually not successful, but an adjustment of up to 20 percent is acceptable.

Resolution: Measure of the detail in an image; the higher the resolution, the higher the amount of detail

Reticulation: Defect in which the ink recedes in certain areas due to incompatibility of the surface energy of ink and substrate.

RGB (Red, Green, Blue ): RGB is an additive color model used in color monitors, conventional photo film and paper to create full color.

RIP (Raster Image Processing): A process using mathematical algorithms to enlarge and print an image. Also, this software often includes "add-on" features, such as color-calibration software, various pattern selections, tools or a print-instruction screen.

Saturation: A measurement of the purity of a colour; the white content of a pure chromatic colour is 0%.

Scan-And-Print: To produce "instant" posters, banners or other wide-format output, this type of inkjet system scales, interpolates and diffuses bitmapped ../image captured by a scanner. The purpose is to reduce the turnaround time and complexity in producing short-term display graphics.

Scanner: A hardware peripheral that illuminates, reads and then converts original text, artwork or film into digital data. Types of scanners include: flatbed or drum, and color or black-and-white.

Scanning: The process of converting a transparency, negative, slide, original or print to a digital file.

Screen Printing: A printing technique involving the forced passage of a paint-like ink through a web or fabric stretched on a frame, to which a stencil has been applied, with the help of a rubber squeegee. The stencil openings determine the form and dimensions of the graphic.

Scrim: Loosely woven polyester fabric coated or laminated with soft PVC; can be opaque (frontlit) or translucent (backlit).

Secondary Colors: Colour obtained by mixing 2 or 3 primary colours.

Service Bureau: A company that typically offers film-output services. Also, a service bureau may offer design and output of digital color graphics.

Sheet/Substrate: The sheet of paper or other material that will be printed on. The largest Iris printers accommodate sheets up to 35 x 47 inches.

Silvering: Small bubbles with a silvery shine between a laminate and a substrate due to insufficient adhesion.

Small Format: Similar to a large-format in processing, just smaller prints.

Smoothing: Averaging values of a pixel with those of neighbouring pixels.

Solvent Inks: Liquid component of ink that uses solvent to carry colorants; solvent inks are more aggressive and affect the surface of the substrate; normally water resistant and more durable than aqueous inks. Solvents also have the benefit of softening up the media surface, which helps colour pigments to bond; thus they can print directly onto vinyl film or vinyl banner; also referred to as “true solvent” or “hot solvent”. As solvent printers emit VOCs production sites must be ventilated.

Special Colors: This refers to colours which are produced using specially mixed inks from one of the commercially available colour ranges such as Pantone, DIC or Focoltone. They are most commonly used when using Two Colour Printing. To print colours outside the range of four colour process it is necessary to use special inks. If for example the exact colour of a company logo could not be achieved from a CMYK mix then it would be necessary to print a fifth plate with the special ink. It is not unusual, where an elaborate effect is required, to print in six or more colours. There are presses which are capable of printing eight different plates in a single run through the machine. It is worth bearing in mind when choosing a colour for a company logo that sooner or later you will want to print a colour brochure using four colour process. A vivid ink which you have chosen from the Pantone book may not have an acceptable CMYK equivalent. You may be forced to change the company colour or swallow the ongoing expense of a fifth plate.

Spectrophotometer: Overall, an instrument that measures the spectral wavelength of color. Also, this instrument calibrates output devices or monitors, and measures dot gain and color density.

Spot Colour: Colours that print as solid blocks without combining with other colours.

Spot White: White ink that is used as an independent colour for printing white text or graphics on a coloured surface or as block-out on a transparent or translucent media.

Stiffness: The stiffness of a plastic or paper the force needed to bend a sheet to a defined angle. Stiffness together with thickness can affect the runability of a printing media in the printer. Paper and polyester are normally stiffer than vinyl.

Stochastic: An alternative to traditional halftone dots, this random-placement dot strategy is used to render enlarged ../image on large-format printing devices. Stochastic dots are uniformly sized "microdots," and their placement and frequency vary with the tone of the image.

Substrate: Ultimately, the material that receives the printed image. Sometimes, this term is called "media."

Subtractive Colors: Cyan, Magenta and Yellow; transparent colors that are combined to reproduce all other colours; black is sometimes added to obtain true, “blacker” black. See CMYK and GCR.

Surfactant: A component in inkjet inks that reduces the surface tension of the liquid.

Swath: A single pass of the printhead assembly over the substrate.

Tagged Image File Format (TIFF): A standard graphic image file format usually generated by scanners.

Tensile Strength: Property that describes the strength of a material; the maximum force per unit width that can be applied to a sheet or strip before it breaks. The higher the tensile strength, the stronger the media.

TGA: Target format developed by Truevision; usually 15 or 24 bit full color ../image, compressed or uncompressed; maximum colors = 16.7 million.

Thermal Film: Heat-sensitive film that carries an image from a thermal ../imageetter. When this clear film encounters heat, it turns black and is transformed to an imaged positive.

Thermal Inkjet: Printing process where ink is heated to boiling point and through expansion is then projected from the head onto the substrate. Thermal print heads are cheaper but need to be replaced more often than piezo heads. Canon, Encad and Hewlett-Packard are manufacturers of thermal inkjet printers.

Thermal Transfer: Printing process where heat is used to transfer resin dyes from a carrier foil onto a substrate.

Thermal-Transfer Printer: A machine that digitally prints by transferring inks (resin or wax based) from a foil ribbon onto media such as paper or vinyl.

Three Colour Printing: Theoretically it is possible to produce an adequate range of colours using just Cyan, Magenta and Yellow. In Four Colour Process Printing the black plate adds shade and depth reducing the amount of ink required. Today this system is.

TIFF: Tag Image File Format; industry standard image file format; "tags" represent image attributes, compression, and color tables; both uncompressed and compressed versions, although compressed is not as portable; maximum colors = 16.7 million.

Tiling: Dividing very large image into smaller sections for ease of handling and printing.

Tint: Reduction in the saturation of a colour by adding white content.

Topcoat: The coating applied to the surface of inkjet or other substrates during the manufacturing process. The topcoat enhances ink adhesion and other performance characteristics; it also helps to control dot gain, drying time and moisture resistance.

Translucent: Diffuse transmission of light. No clear image contours can be seen.

Transparency: The preferred medium for photographs intended for printing. Transparencies generally have sharper image and better colour than photographic prints. The three most common sizes are 'five-by-four', 'two-and-a-quarter' (both in inches) and 35mm - the same size as your holiday slides.

Transparent: Transmission of light or certain colours with no or minimal diffusion or scattering.

Trapping: The process of creating an overlap between abutting colors to compensate for imprecisions in the printing press.

Trim Size: The dimensions of a page, including the margins.

TrueType Fonts: Scalable typefaces for Windows and Macintosh software.

Tunnelling: Delamination in the shape of waves of straight tunnels due to insufficient adhesion or tensions in the substrate or laminate.

Twain: Communication protocol between digital imaging devices (scanners, cameras etc.) and PCs.

Two Colour Machine: A press which prints two colours during one pass through the machine. It is possible to print four colour process by printing Cyan and Magenta, changing the plates and then sending the sheets through again to print the Yellow and Black.

Two Colour Printing: Two colour printing is commonly used for stationery because of its cost-effectiveness. The typical design includes a special colour such as a Pantone ink along with black. The special ink is for the 'company colour' for use on the logo and the black is for text. In addition, tints of both inks could be used to produce variations of the colour and greys respectively. For example, if a strong blue is chosen as the main colour then the opportunity exists to have a pale blue tint, perhaps as a background 'ghost' image. A range of greys is also available from tints of black. Two colour printing can be an economic way of producing brochures and catalogues if full-colour ../image are not required. There are creative options such as duotones which can be considered if the subject matter is suitable.

Type 1 Fonts: Adobe's industry-standard outline font technology that enables type to be scaled to any size while staying sharp and clear. More than 20,000 Type 1 typefaces are available from vendors worldwide.

Typography: A specific and distinct style of lettering, also called type, type style or font.

UV Curing Inks: Inks that cure and create a bond to the substrate through polymerisation effected by ultra-violet irradiation from lamps on either side of the printhead assembly; commonly found on flatbed printers.

UV Filter: Laminate with added UV inhibitors that reduce a certain amount of UV light to prevent rapid fading of colorants.

UV Inks: Inks that contain pigments or other methods to resist UV fade from direct sunlight and other UV light sources.

UV Resistance: The resistance to fading under direct sunlight and other UV light sources.

UV Varnishing: A method of adding a gloss finish to printed surfaces. The advantage of UV varnishing is that it is similar to printing an extra colour and can be applied to selected areas to produce special effects. The UV refers to the Ultra-Violet lamp under which the varnished sheets pass for rapid drying.

Viscosity: Measurable resistance to flow in fluid or semi-fluid substances; increases with decreasing temperature.

Volatile: Ingredient of an ink or an adhesive subject to evaporation at relatively low temperatures.

Waterproof: Substrate resisting dissolution and decolourisation when immerged into water.

White Point: The lightest tone in an image.

Wicking: Absorption of ink along the fibres of paper, also called spider web effect.

WYSIWYG (What You See Is What You Get) (Pronounced Wizee-Wig): An acronym meaning that a computer file's output is actually what is seen on the monitor.