Print Glossary Printing lingo explained for the common people 1-bit Black & White Bitmap A type of bitmap image that contains only pure black or pure white pixels. Used in situations where shades of grey are not present as with scanned text or line drawings. Should be scanned at high resolutions above 1200dpi. Acrobat Adobe software product that converts page layouts into a standard format based on the Postscript language. It tranlates text, vector and bitmap information into PDF files which can then be viewed and printed on any machine regardless of platform. A useful format for printers as all images and fonts are contained and compressed in the same file enabling fast transfer over the internet. Files have a .pdf extension. Aliasing/Anti-Aliasing Aliasing is the visual stair stepping of edges (jagged edges) that occurs in an image when the resolution is too low. Anti-Aliasing is the smoothing and removing of aliasing effects by electronic filtering and other techniques such as blending of hard edges. Alpha Channel An image editing software channel containing information used to mask or partially reveal areas of a bitmap image. Useful to remove backgrounds from objects. Ampersand The "&" symbol which stands for the word "and". It is actually a stylistic combination of the letters that make the Latin word 'et' which means 'and'. Art Paper A smooth coated paper obtained by adding a coating of china clay compound on one or both sides of the paper. Blanket A rubber-faced sheet onto which ink is transferred prior to that ink being transferred to the sheet to be printed. The process 'offset' is so called because the ink is picked up by the blanket from the inked plate and then 'offset' or transferred onto the paper. Banding Patterns (stripes) on a print caused by insufficient colour or greyscale ranges within the output devices image processor, or insufficient information contained within the original scan. Creates harsh, well defined transitions between different tonal ranges, where a smooth transition was required. Beziér Curve Curved line segments created by establishing endpoints or anchor points, and at least one transient point or node. A common method used to create irregular lines and shapes in design software. Black Generation The calculation determining the degree of black ink to be added when separating an RGB colour image into CMYK colours. Bitmap A bitmap image is composed of a grid of dots (also called pixels or bits). All the digital photographs on your hard drive are bitmaps. If you zoom right up close in your software applications you will actually notice the image is composed of squares those are the bits. Bitmap images cannot be easily scaled up in size without loss of quality. Bleed When an image or design goes right to the edge of the printed sheet. The job is printed on oversize paper stock and the page's design extends around 3-5mm beyond the intended page size. The bleed is then trimmed off in the finishing process. Calibration The setting of computer system components to a standard which will produce the same colour results on each unit. Colour calibration is necessary on display monitors to achieve the same colour results on the printed output. Camera Ready An outdated term meaning artwork that doesn't need further alterations by the printer. The artwork was then used to make the printing plates via a photographic process, hence the term camera ready. CCD Charged Coupled Device. Light-detection device used in many scanners, digital cameras, and video cameras that generates electrical current in direct proportion to how much light strikes areas of the sensor. A CCD array is an arrangement of CCD sensors mounted in close proximity that allows for the simultaneous capturing of many pixels with one exposure. Cloning The process of sampling one area of an digital image to cover unwanted areas, e.g. replacing scratches with surrounding background to re-touch the image. Coated Stock A printing paper or card manufactured with a transparent, smooth layer added to one or both sides that changes the look of the final printing. Coatings are normally defined as gloss, semi-gloss or matte surfaces. Color Proof A colour sample that attempts to represent the final printed image that will result when a piece is offset printed. Colour proofs can be generated from film separations prior to using the separations to make printing plates. Continuous Tone An image in which the subject has continuous shades of color or grey without being broken up by dots. Continuous tones cannot be reproduced in that form for offset printing but must be screened to translate the image into dots. CMYK - see Four Colour Process. Drill If your printing job has to be put in a 3 ring binder or needs to be hung on a shop display you need some hole "drilled" into it. The machine used to do this is very similar to the drill presses used in other industrial situations. Duotone A black and white photograph reproduced using two halftone negatives and printed in black and one other colour ink. EPS Stands for Encapsulated Postscript. An EPS is a graphics file format that can contain vector and bitmap information. An EPS consists of a "header graphic" which is the part you see in your software program, and  the postscript information that contains the data for all the objects contained in the file. EPS files can only be printed to a Postscript Printer. If you print and EPS to a non-Postscript printer only the low resolution header graphic will print. Film Synthetic film produced by an imagesetter from the digital files used in a projects design. Is then used to make a printing plate. For offset printing negative film is produced such that light values are reversed to dark and vice versa. Fit The alignment of printed colours on a sheet. Poor fit means colours do not line up correctly resulting in white gaps on the job. Tight fit means the design of the print job requires special attention when being printed and may need trap being added to the job. Sometimes referred to as registration However, registration refers more correctly to the consistent position of the print image relative to the actual stock's dimensions compared to consecutive sheets in the press. Flexography Printing from a rubber roller, i.e. direct rotary printing using resilient raised image plates. Typically used in the packaging industry for printing on heavy weight stocks. Foiling/Foil A letterpress based printing process that transfers a very thin layer of shiny metallic alloy onto the printed surface. Available in many different colours and patterns (including holographic) and used primarily to add a traditional or flamboyant element to a job's design. Greeting cards are a good example of this printing application. Font Historically, an collection of metal letters and numbers, all the same size and type with a predetermined amount of each letter or number. Today, the term refers generically to type or letter styles. Four Colour Process This is the standard printing method that uses the four process colours of Cyan (C), Magenta (M), Yellow (Y) and Black (K). These four inks are combined in varying percentages to create a broader spectrum of colour. The actual number of possible colours in the CMYK colour space is 100 x 100 x 100 = 1 000 000. This is not including black as this is not a colour but only adds shade to individual hues. Full Colour - see Four Colour Process Gamma A mathematical curve representing both the contrast and brightness of an image. The steepness of the curve indicates greater contrast. Gamut The range of colors that can be captured or represented by a device. When a color is outside a device's gamut, the device represents that color as some other color. The RGB gamut contains a possible 16 777 216 colours and the CMYK gamut contains only 1 000 000 colours (not including shades that use black ink). GIF Graphic Interchange Format. An image format type generated specifically for computer use. Its resolution is usually very low (72 dpi) making it largely unusable for printing purposes. Graphics Tablet A device that allows the user to draw on a tablet using a pen or stylus which is then digitised and translated into the graphics application of the user. A more naturally intuitive pointing device than a mouse. Can be used to simulate illustration and airbrush techniques. Gravure A rotary printing process where the image is etched into a metal plate attached to a cylinder. The cylinder is then rotated through a trough of ink, after which the etched surface is wiped clean by a blade leaving the non-image area clean. The paper is then passed between two rollers and pressed against the etched cylinder drawing the ink out by absorption. Greyscale A bitmap image format that containing shades of grey values as opposed to only pure black and pure white. This format is used for single colour usually black photographs and images. There are 256 possible values of grey from white to pure black. Halftone A photographic print is referred to as being "continuous tone" as the shades of grey are areas of flat or continuous tone. Printing presses can only print one colour ink at any given time so the photo has to be converted into a different format. The halftone format converts the discreet shades of grey  into an array of round dots. Dark areas have few dots, light areas have many dots. In full colour printing these halftone dots are further separated into which colours belong on the cyan, magenta, yellow and black plates. Histogram A graphic representation of the distribution of tones within an image. The horizontal axis represents each pixel value possible from black to white. The vertical values indicate the number of pixels in the image that occur at each value level. HSB Hue Saturation Brightness. A colour model that utilises Hue, Saturation and Brightness as the three coordinates. Hue is the dominant colour, Saturation is the purity of the colour, and Brightness is a neutral scale of how light or dark a colour is. Imagesetter An imagesetter is a high resolution photo-imaging device that prints digital computer files to film (like the negatives used in traditional camera). This film is then used to make printing plates. Imposition The arrangement of pages on a printed sheet, which when the sheet is finally printed on both sides, folded and trimmed, will place the pages in their correct order. Indexed Colour A colour system that defines a palate of colours to be used in a specific image. This makes the file size small and manageable. JPG or JPEG Joint Photographic Experts Group. Standardised image compression format developed by the Joint Photographic Experts Group. Used for compressing full colour and greyscale images. The standard format for digital camera files. Kelvin A unit of measure on the absolute temperature scale. Defines the quality of a light source by measuring the absolute temperature of a black body that would radiate equivalent energy. Colour calibration software can help determine the Kelvin value of your monitor and adjust the display settings to suit the Kelvin rating of the light bulbs used in your office environment. Kerning Adjusting inter-character spacing of letters. Typically for pairs of letters that need special spacing to make them more easily recognisable and readable. Landscape The orientation of a page so that the longest edge is horizontal. Leading All the characters in a page of type rest on an imaginary line called a baseline. Leading is the space between one baseline and the next. The origin of the term is found in the history of printing where pages were set using metal type. Long strips of lead of equal thickness were used to sit the lines of metal type on, hence "Leading". Software programs often refer to leading as "line spacing". Letterpress A method of printing that was used exclusively up until the 1980s and the invention of offset printing. The printing "plate" has a raised surface composed of raised metal letters and other elements which is then inked and pressed mechanically onto the printed sheet. Line Art Single colour logos, drawings or diagrams that consist of only black and white without intermediate greyscale information. See also 1-bit Black & White Bitmap. Lithography A method of printing from a plane surface. The printing image is ink-receptive, the non-printing areas are ink repellant. Lossless/Lossy Compression Lossless compression will retain all of the file's original image data. The TIF format using LZW compression is considered and example. Lossy compression will sacrifice user-definable amounts of image quality and detail to reduce file size. An example is JPEG compression. LPI Lines Per Inch. The number of lines per inch on a halftone screen. As a general rule, the higher the lpi, the higher the printed resolution and quality. LZW The Lempel-Ziv-Welch image compression technique. Macro Mode Setting that allows a camera to focus on objects which are very close. Make Ready The time spent in making ready the level of the printing surface by placing packing under the form or around the impression cylinder. Also, the process in getting an offset press ready for printing. Mask To block off a background or other area, so that the unmasked area can be printed. Also, to enclose a portion of an image so that it can be manipulated without affecting the unmasked area. Metal Foil A highly reflective metallic effect used on printed items. A metal block is produced with the design required in raised relief. A mechanical process then stamps the block under high pressure onto rolls of thin metallic foil which thus transfers the foil image onto the printed stock. A large variety of colours and finishes including matt, gloss and holographic. Metallic Inks Gold and silver semi-reflective inks used for special effects in print design. In most cases should be printed on coated gloss art stock or high gloss cast coated otherwise the ink is absorbed into the stock leaving a dull lustre finish. Midtones Tones in an image that are in the middle of the tonal range, between the lightest (highlights) and darkest (shadows) areas. Moiré An undesirable that appears on printed pictures that were scanned from an already printed source. It appears as a regular pattern or clumping of colours. A moiré pattern is created by the juxtaposition of two repetitive graphic structures, e.g. rows of dots (as with halftone screens) intersecting at an angle. Native Files The original computer files in their original application file format as opposed to an exported file format such as postscript print to disk format or pdf format. Negative - see Film. Pantone Matching System A system of colour that ensures repeatable mixing of specific spot colour inks no matter where or on what stock the job is printed. Typically a printer will show a customer a PMS book in order to choose a specific spot colour, identified by a number, which is to be used in their print job. The book also contains information on the the exact measurements of component inks required to reproduce that colour. This way the customer and printer knows exactly which colour is to be achieved. PDF Portable Document Format. An electronic document format from Adobe that allows the distribution of digital files across any operating system or platform. Displays a document as originally designed and formatted without having the original software application or fonts on the viewing computer. Perfect Binding A common method of binding paperback books. After the printed sections have been collated, the spines will be ground off and the cover glued on. The finished product is then trimmed flush with the cover. Pixel The smallest unit of data in a digital image. Together, the small discrete elements constitute an image that can be seen on a monitor or printed on a substrate. A pixel's code contains information relating to color and placement within the larger image. Pixelated An undesirable effect caused by images or lines being rendered at too low a resolution. Produces a stair stepped effect giving lines or edges a rough appearance. Pixels Per Inch (PPI) A measure of the density of scanned pixel information in an image. The finer the optics of the scanner, the higher the scan resolution. Point A unit of measurement used in the graphic arts industry. There are 12 points to a Pica. One point equals approximately 1/72 inch. Portrait The orientation of a page so that the longest edge is vertical. Postscript A digital page description language used by laser printers and some inkjet printers and colour copiers. When you print to a postscript printer, the printer turns the page layout into a series of commands which the printer translates into toner on paper. Only postscript printers can print EPS graphics and Postscript fonts. Most consumer printing devices do not support Postscript as it is really only necessary for use with printing industry applications. Pre-Flighting A process of checking a job for possible problems before the job is sent for final output. This process is used to find problems such as missing fonts, postscript errors and colour problems. Prepress The process of getting an image ready to go on press. Digital prepress denotes the entire preparation of a digital file for printing in either a digital or conventional system. Process Colour The process colours (Cyan, Magenta, Yellow, and Black) are used in traditional colour printing to reproduce a full colour range. Proof A laser printout or as such used to evaluate the typesetting layout and design of a job prior to printing. Quantity Confusion can occur when the item can be printed in multiples on one sheet, say 2 or 3 up. If a customer asks for 1000 copies and provides the job 2up the printer will assume 1000 finished items are required and print only 500 sheets. The customer may be disappointed because they meant for 1000 sheets to be run and actually needed 2000. To avoid this confusion quantity always refers to the amount of finished size items required. Raster The process of rendering an image or page, pixel by pixel, in a sweeping horizontal motion, one line after another. Has nothing whatsoever to do with Bob Marley. Raster Image An image that is defined as a collection of pixels arranged in a rectangular array of lines of dots or pixels. See Bitmap. Rasterization Changing vector-type image information to raster image information. Registration - see Fit. Resampling Changing the resolution of a bitmap file without altering its physical size. Resolution The quality of a graphic file is measured by the number of pixels or dots per inch (dpi) the image contains. A high resolution file might typically be 300 dpi and is suitable for printing jobs. A 72 dpi image is considered to be a  low resolution image and is useful for website design. The image resolution changes as you scale the picture up and down in your graphics program. The term also applies to a laser printers output capabilities, which range from 300dpi to 2400dpi plus form imagesetters. RGB A color model using red, green, and blue - the additive primary colors. Computer monitors and televisions use RGB data to create screen images. RTF Rich Text Format. A format that accepts both text and images, and retains text formatting and page layout. Set-Off The accidental transfer of the printed image from one sheet to the back of the sheet above it. Saddle Stitch A method of binding where the folded pages are stitched through the spine from the outside, using wire staples. Usually limited to about 64 pages. Scoring Heavy card weight stock can get unsightly bumps when folded. To prevent this a score is made along the fold line using a scoring wheel on the printing press. A shallow indentation is thus made ensuring the item folds neatly. Separations The actual splitting of an image into the colors that will be used in the printing process. Normally, Cyan, Magenta, Yellow and Black (CMYK) are the separations for 4-color printing. Serif/Sans-Serif Refers to different styles of letter forms. Serif typefaces have the little hats and tails on the ends of the up and down strokes and are more typically used for large bodies of text such as in books and news articles. Sans-serif (sans meaning without) typefaces don't have the hats and are ideal for headings and titles. Times New Roman is a serif typeface. Arial is a sans-serif typeface. Signature In offset printing, the printed sheet containing a number of different pages that have been arranged to allow; through folding, trimming, and binding; the creation of a multi-page finished piece. Spot colours These colours are printed as solid areas and used when fewer than four colours are needed or when the four-colour process (CMYK) is unable to accurately reproduce a colour. TIFF (or TIF) Stands for Tagged Image File Format and is the preferred file format used for bitmap images in the graphics industry. The best format to use when you don't want to lose quality in your image. Tint A percentage of a solid ink. Tints are created by using a screen to create the impression of a lighter colour when the ink is printed onto paper or another medium. Tracking The adjustment of the overall spacing between all text characters in a word or words. Tight means letters are close together, loose means letters are far apart. Trapping Is the implementation of small amounts of overlap on elements of a page's design to prevent conspicuous areas of whitespace from appearing on print jobs. To clarify let's look at an example. When a large blue title is printed on a red background, a hole (white space) is created in the red plate where the blue letter shapes will fall (otherwise the blue and red ink would mix resulting in a "purplish" blue). For one reason or another it can be very difficult for the printer to perfectly fit the blue shape into the red hole and unsightly white space can appear. For this reason a thin outline of blue is added to the edge of the letter shape that will overlap with the red image thus fixing the problem. Typeface The style and design of the letter forms in an alphabet. Vector Image A computer image that uses mathematical descriptions of paths and fills to define the graphic, as opposed to individual pixels. Can be scaled to any size without loss of quality. Work and Turn A method of printing where pages are imposed in one form or assembled on one film. One side is then printed and the sheet is then turned over sidewise and printed from the other edge using the same form or plate. The finished sheet is then cut to produce two complete copies. Work and Tumble A method of printing where pages are again imposed together. The sheet is then printed on one side with the sheet being turned or tumbled from front to rear to print the opposite side. WMF Windows Metafile Format. Vector graphics format used in Microsoft products. Format of choice for Microsoft clip-art collections. X-height The height of a letter excluding the ascenders and descenders. As an example, "x", which has neither ascender nor descender. Zip To compress a file using WinZIP or similar compression software. Commonly used to reduce the size of a file and to group many files into a single archinve in order to speed transmission over the internet.