Caliper: The thickness of paper, usually expressed in thousandths of an inch (mils). Also, a device on a sheetfed press that detects double sheets or on a binding machine that detects missing signatures or inserts.
Camera-Ready: Copy and all other printing elements are ready for photography.
Carbonless Paper (NCR): Paper coated with chemicals that enable transfer of images from one sheet to another with pressure from writing or typing.
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.
Chromolin: A fast proofing system which uses powder as opposed to ink.
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 Fidelity: How well a printed piece matches the original.
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: 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: Symbols placed in the margin outside the image area indicating where to trim, perforate or fold.
CTP: Abbreviation of computer-to-plate; a process of printing directly from a computer onto the plate used by a printing press.