Print Glossary

At times it must seem as if printers use a different language. The terms used can be difficult to understand. We have created a glossary of some common (and not-so-common) Printing Terms:

against the grain:
At right angles to the grain direction to the paper.

art paper:
A common term used to describe a range of smooth papers with a filled surface.

‘A’ sized paper:
Paper sizes are based on dimensions of a large A0 sheet. Letterheads are commonly produced on A4 sized paper.

application:
A computer program designed for a particular use, such as a word processors such as Microsoft Word or page layout applications, such as Quark Xpress or Adobe Indesign.

artwork:
A process which follows the initial design stage which makes rough ideas into a print-ready form.

a/w:
Abbreviation for artwork.

backing up:
Process of printing on the second side of a printed sheet.

binding:
Process of fastening papers together.

bitmap:
A grid of pixels or printed dots generated by computer to represent type and images.

blanket:
Thick rubber sheet that transfers ink from plate to paper on the press.

blind emboss:
Impression of an un-inked image onto the back of a sheet which produces a raised ‘embossed’ image on the front of the sheet.

bleed:
The printed image extends beyond the trim edge of a sheet or page. A bleed may occur at the head, front, foot and/or gutter of a page.

blend:
A smooth transition between two colours, also known as a graduated tint or gradient.

bond paper:
A grade of paper suited for letterheads, business forms etc.

case bound:
A hardback book made with stiff outer covers. Cases are usually covered with cloth, vinyl or leather.

cast coated:
Coated paper with a very high gloss enamel finish

choke:
A method of altering the thickness of a shape by over exposure in processing or by means of a built-in option in some computer applications.

clipart:
Graphics saved in ready-to-use computer files. these are normally vector illustrations and not photographic images.

clipping path:
An outline, embedded into the file, that tells an application which areas of a picture should be considered transparent.

CMYK:
Abbreviation for cyan, magenta, yellow and key (black), the 4 process colours, which combined together in varying proportions can be made to produce the full colour spectrum.

collating:
Gathering together sheets of paper from a book, magazine or brochure and placing them into the correct order.

colour separation:
Process by which a continuous tone colour image is separated into the four process colours (CMYK) for print production.

concertina fold:
A method of folding in which each fold opens in the opposite direction to its neighbour, giving a concertina or pleated effect.

continuous stationery:
Forms which are produced from reels of paper and then fan folded. these can be either single or multi-part forms.

crash number:
Numbering paper by pressing an image on the first sheet which is transferred to all parts of the printed set.

crease (score):
To mechanically press a rule into heavy paper or board to enable it to be folded without cracking.

creep:
Phenomenon when middle pages of a folded section extend slightly beyond the outside pages.

crop:
To trim the edges of a picture or page to make it fit or remove unwanted portions.

crop marks:
Lines near the margins of artwork or photos indicating where to trim, perforate or fold.

CTP:
Abbreviation of computer-to-plate; a process of imaging directly from a computer onto the plates used by a printing press.

cyan:
One of the four process colours, also known as blue.

deboss:
Image pressed into the front paper so it lies below the surface.

density:
The degree of darkness of light absorption or opacity of printed images.

die-cutting:
Process of using sharp metal rules on a wooden block to cut out specialised shapes such as pocket folders or unusual shaped flyers etc.

digital printing:
Benefits are for very short runs or for personalised print. some feel that the quality is not yet to the standard of offset litho, however, some feel that it is.

digital proof:
A high quality colour representation of the finished print, produced for customer inspection for errors that can be corrected prior to final printing.

dot gain:
A printing defect in which dots print larger than intended, causing darker colours or tones; due to the spreading of ink on stock. the more absorbent the stock, the more dot gain. can vary by type of ink also.

DPI:
A measure of the quality of an image from a scanner or output resolution of a printer. The more dots per inch, the higher the quality will be but the larger the file size the slower it will process.

duotone:
A method of enhancing a mono image using two colours.

drilling:
Drilling of holes in product which will allow insertion over rings or posts in a binder of some sort.

dummy:
A mock-up made to resemble the final printed product which uses the proposed grade, weight, finish and colour of paper.

embed:
Implies the inclusion of elements and data into a computer file necessary to maintain or change the elements when used remotely.

embossing:
A process performed after printing to stamp a raised image into the surface of paper, using engraved metal embossing dies, extreme pressure, and heat. embossing styles include blind, deboss and foil-embossed.

EPS:
An acronym for Encapsulated PostScript, a computer file format widely used by the printing and graphics industries.

file format:
The system by which data is held in a particular type of computer file.

flush:
To align, to be even with. (flush right to a margin for example).

foil stamping:
A metallic finish, or other embossed finishes applied by specialist equipment.

font:
One of a range of styles/typefaces in which lettering can be produced during the type setting stage, e.g. Times New Roman.

four colour process (CMYK or full colour):
Reproduction of full-colour photographs or art with the four basic colours of ink (cyan, magenta, yellow, black).

font matching / font substitution:
A sometimes undesirable process used when a chosen font is not available, the closest possible match is made, sometimes causing reflow of the text or other errors.

full colour (CMYK or four colour process):
Reproduction of full-colour photographs or art with the four basic colours of ink (cyan, magenta, yellow, black).

gutter:
Line or fold at which facing pages meet.

GSM:
Paper weight is measured in grams per square metre.

graphics file:
General term used for a computer file containing a picture: photographic image, illustration etc.

greyscale:
Shades of grey ranging from black to white; in printing, greyscale appears only on the black plate.

grippers:
Metal fingers which hold paper and carry it through printing impression to the delivery end of the press.

gusset:
Expandable portion of a pocketed folder or envelope.

halftone:
Picture with varying shades of tone created by varying size dots.

head margin:
The white space above the first line on a page.

hickey:
Spot or imperfection in printing.

hue:
The main attribute of a colour which distinguishes it from other colours.

image area:
Portion of paper where ink appears.

imposition:
Positioning pages in a press-ready form so that they will be in the correct numerical sequence after folding.

imagesetter:
A device that plots high-resolution images which have been processed by a RIP, onto film or directly onto plate.

indicia:
Postal information place on a printed product.

ivory board:
A smooth high white board used for business cards etc.

jog:
To shake a stack of papers, either on a machine or by hand, so that the edges line up. Also referred to as knocking-up.

JPEG:
An acronym for ‘Joint Photographic Electronic Group’. a common standard for compressing image data.

job ticket / job sheet:
Alternate names for a works order.

justified:
Text which is flush to both the left and right margins.

kerning:
The adjustment of spacing between certain character pairs, A and V for example, to obtain a more pleasing appearance.

kiss-cut:
To die-cut but not all the way through the paper – commonly used for peel off stickers.

knockout:
A shape or object printed by eliminating (knocking out) all background colours.

kraft paper:
A tough brown paper used for packing.

laminate:
A thin film coating which is applied to the paper or board to give a more glossy or matt appearance.

layout file:
The file created by computer application software which contains all the imported elements and where all the design and layout of a document are performed.

lithographic printing:
A printing process based on the principle of the natural aversion of water to grease. the areas to be printed receive and transfer ink to the paper, the non-printing areas are treated with water to repel the ink.

loose leaf:
A method of binding which allows the insertion and removal of pages for continuous updating.

lpi:
Lines per inch – refers to the quality of a halftone screen. it is important to distinguish it from dpi which refers to the resolution of a device or image. commonly lpi is used at exactly half of the dpi of the device or image, i.e. 300dpi would equal 150lpi.

line art / line copy:
Copy which can be reproduced without using halftones.

magenta:
One of the four process colours, also known as red.

make-ready:
The work associated with the set-up of printing equipment before running a job.

plate:
A metal sheet with a specially coated ‘emulsion’ on its surface which when exposed through a film mask or by CTP process will produce an image. when the plate is loaded onto printing press it then reproduces this image using inks onto the paper.

micrometer:
Instrument used for measuring the thickness of paper.

moiré:
An undesirable grid-like pattern caused by the misalignment of dots on a printed document. this can occur when printing or sometimes when scanning from pre-printed material.

matt:
A non glossy finish.

NCR (carbonless paper):
An acronym for ‘No Carbon Required’. A Paper coated with chemicals that enable transfer of images from one sheet to another with pressure from writing or typing.

origination:
A term used to describe all of the processes which prepare a job for the printing stage.

outline paths:
A term used when converting a font or graphic into a mathematical vector format. can also be called ‘curves’.

offset printing:
A method in which the plate or cylinder transfers an ink image to an offset or transfer roller, which then transfers the image to stock.

over-run:
Copies printed in excess of the quantity specified in the order.

page count:
Total number of pages, including blanks and printed pages without numbers.

perfecting:
Process of printing both sides of one sheet during a single pass through the press.

perfect binding:
A bookbinding method in which pages are glued rather than sewn to the cover. used primarily for paperback books.

point (pt):
A measurement for the size of fonts and the thickness of rules. one point equals one seventy-second of an inch (0.3515mm).

proof:
A representation of the finished print, produced for customer inspection for errors that can be corrected prior to final printing.

progressives:
Colour proofs taken at each stage of printing showing each colour printed alone and then superimposed on the preceding colour.

quotation:
An offer to produce a job for a specific price calculated from job specifications provided by the customer.

recto:
Right hand page of an open publication.

registration marks:
Crosses or reference marks on the page used to align overlaying colours (‘registration’). Also known as trim marks or crop marks.

reversed-out:
Type appearing white on a black or colour background, either a solid or a tint.

resolution:
The number of dots per inch (dpi) in a computer-processed document. the level of detail retained by a printed document increases with higher resolution. ppi (pixels per inch) for an image.

RIP (raster image processor):
Computer used to create an electronic bitmap for actual output. this may be built into an output device or may be separate.

RGB:
An acronym for red, green and blue. RGB is a colour model used for computer monitors and colour video output systems. colour separations for litho printing can not be made directly from RGB files and need to be converted to CMYK first.

rosette:
The formation created by the dots that make up four-color images. The dots, in magenta (red), cyan (blue), yellow, and black, overlap each other in a cluster. because the dots are not perfectly round, and because they are turned at angles to each other, this cluster resembles the arrangement of petals in a rose.

saddle stitch:
A binding process in which a pamphlet or booklet is stapled through the middle fold of its sheets using metal wires.

scanning:
The process of converting a hard copy into digital data ready for editing and design. the quality of the scan is dependent on the quality of the original, the scanning equipment and software as well as the experience of the operator!

score (crease):
To mechanically press a rule into heavy paper or board to enable it to be folded without cracking.

self-cover:
The paper used inside a booklet is the same as that used for the cover and is generally printed on the same

step-up:
A term used to describe the positioning of documents several times onto the same sheet of paper to avoid paper wastage. it’s also known as imposition.

stock:
A term for the material any project is printed onto.

spot colour:
Spot colour is not made using the process colours. instead the colour is printed using an ink made exclusively. each spot colour therefore requires its own separate printing plate. spot colours do not apply to digital printing as such devices can only reproduce from the four process colours; cyan, magenta, yellow and black.

spread:
Two or more adjoining pages that would appear in view on sheet.

solid:
An area on the page which is completely covered by the ink.

TIFF:
Acronym for Tagged Image File Format. TIFF (.TIF) pictures can be black-and-white line art, greyscale or colour. this is a widely used format for image/photographic files but is unsuitable for text unless its is created at a very hi-resolution.

tint:
An area of tone made by a pattern of dots, which lightens the apparent colour of the ink with which it is printed.

trapping:
A slight overlapping between two touching colours that prevents gaps from appearing along the edges of an object because of misalignment or movement on the printing press.

turnaround time:
Amount of time needed to complete a project.

UV varnish:
A liquid laminate that is bonded and cured with ultraviolet light.

varnishing / sealing:
The application of a varnish/sealant to a surface to offer protection against marking & improve overall appearance.

verso:
Left handed page of an open publication.

wash up:
To clean ink from rollers, fountains and other components of a press.

wire-o binding:
A method of binding books with a spiral wire along the binding edge that will allow the book to lay flat.

work and tumble:
To print one side of a sheet of paper then turn the sheet over from gripper to back using the opposite gripper edge but the same side guide to print the second side.

work and turn:
To print one side of a sheet of paper then turn the sheet over from left to right and print the second side using the same gripper edge to print the second side.