Glossary of Printing Terms

Accordion fold
Folding paper by bending each fold in the opposite direction of the previous fold creating a pleated or accordion effect.

Any part of a lower case letter which rises above the main body of the letter such as in “d”, “b” and “h”.

Base line
The imaginary horizontal line upon which stand capitals, lower case letters, punctuation points, etc.

Any element that extends up to or past the edge of a printed page.

Center spread
The two pages that face each other in the center of a book or publication.

Comb Binding
Where a plastic “comb” is attached through holes punched along the side of a stack of paper. Commonly used for reports, proposals and manuals. Documents bound with a comb have the ability to lay flat and can roatate 360 degrees.

Crop marks
Small printed lines around the edges of a printed piece indicating where it is to be cut out of the sheet. Sometimes referred to as cut marks.

A term that describes that portion of lower case letters that extends below the main body of the letter, as in “p”.

The smallest individual element of a halftone.

Dot gain
A term used to describe when dots are printing larger than they should.

A two-color halftone reproduction generated from a one color photo.

The molding and reshaping of paper by the use of special metal dies and heat, counter dies and pressure, to produce a raised image on the paper surface.

The surface quality of a paper.

Gate fold
A three or four panel fold where the two outside panels fold inward to meet in the center. In an open gate fold, there are three panels, the bottom of which is twice the size of the folded panels. In a closed gatefold, there are four panels of roughly equal size where the outer panels are folded inward together.

A blank space or margin between components on a printed piece or press sheet.

Using small dots to produce the impression of a continuous-tone image. The effect is achieved by varying the dot size and the number of dots per square inch.

The narrowing of space between two letters so that they become closer and take up less space on the page.

Space between lines of type. The distance in points between one baseline and the next.

Offset printing
The most commonly used printing method, where the printed material does not receive ink directly from a printing plate but from an intermediary blanket that receives the ink from the plate and then transfers it to the paper.

The numbering of individual pages in a multi-page document

Perfect Binding
A binding process where the signatures of a book are held together by a flexible adhesive.

Process printing
A system where a color image is separated into different color values (cyan, magenta, yellow and black or CMYK) by the use of filters and screens or digitally with a software program and then transferred to printing plates and printed on a printing press, reproducing the original color image.

Register marks
Any crossmarks or other symbols used on a press sheet to assure proper registration.

The color space of Red, Green and Blue. These are the primary colors of light, which computers use to display images on your screen. An RGB computer file must be translated into the CMYK (the primary colors of pigment) color space in order to be printed on a printing press.

To crease paper with a metal rule for the purpose of making folding easier.

The overlapping of one color over a different, adjacent color to ensure that no white space is visible where the two colors meet, especially when there are slight variations in the registration of the two colors during the printing process. Or the process of printing wet ink over wet or dry previously printed ink.

Trim marks
Marks placed on the printed sheet to indicate where cuts should be made.

UV Coating
A very shiny and durable high gloss coating applied to printed material. Applied as a liquid then cured with ultraviolet light.

A translucent mark or image that is embossed during the papermaking process, or printed onto paper, which is visible when the paper is held up to the light.

Zip file
Zipping a file compresses one or more files into a smaller archive. It takes up less hard drive space and less time to transfer across a network or the internet.