useful information

Glossary - H

Hair-line rule

The thinnest rule that can be printed.

Hair-lines

Thin strokes of a typeface.

Halation

Spreading of light around the highlight in an image.

Half up

Artwork one and a half times the size which it will be reproduced, which would be one third down.

Halftone

A printed picture that uses dots to simulate the tones between light and dark. Because a printing press cannot change the tone of ink, it will only print the ink colour being used on press. This works well for printing text or line art: the press simply puts a full dose of ink for each letter or line on the paper, creating small solid areas of ink. But black-and-white photographs are continuous tone images, and printing a photograph this way would have the same result: large solid areas of ink. White areas of the photograph would have no ink; black areas would have black ink; and grey areas would have black, not grey ink. The halftone mimics the continuous tone of a black-and-white photograph by converting the picture to dots. Photographing a continuous tone image through a screen creates a duplicate image made of dots. Darker areas of the photograph have bigger dots and lighter area of the photograph have smaller dots. To the human eye, the black of the dots blend with the white of the paper to create shades of grey. The result is strikingly similar to the continuous tone of a photograph.

Halftone cell

An arrangement of dots used to simulate a traditional halftone on a digital printer. Because an imagesetter can only produce black dots, it must simulate shades of grey by turning some of the dots in the cell on or off. If half the dots are on, it appears to be 50% grey. Since PostScript can handle 256 shades of grey, the optimal halftone cell is 8 x 8 (8 dots wide times 8 cells high equals 256 dots total). Therefore, the optimal line screen for a given printer is its dpi divided by 8 (e.g. 600 dpi can produce a halftone pattern 75 lines per inch). Unfortunately, arcane matters beyond the scope of this document complicate this simple formula.

Halftone dot

Basic unit in a halftone. Various sizes of halftone dots recreate original continuous-tone copy for reproduction.

Halftone engraving

Relief printing plate made from a halftone negative.

Halftone negative

Negative film used to shoot continuous-tone copy through a halftone screen.

Halftone positive

Film resulting from exposure through a halftone negative.

Halftone process

Process of reproducing continuous-tone copy by shooting it with a screen that separates the image into a series of dots.

Halftone screen

Converts the original grey tones of continuous-tone copy into halftone dots for reproduction.

Halo effect

Occurs when ink builds up around printed letters or halftone dots, giving the centre a lighter appearance. Also called Halation.

Hand-engraving

The art of engraving done freehand using specially shaped and contoured hand-held tools and requiring a considerable degree of artistic talent.

Hanging indent

Where the first line of a paragraph is set full out to the column, and the remaining lines are indented by 1 em.

Hanging punctuation

Punctuation that is allowed to fall outside the margins instead of staying within the measure of the text.

Hard copy

Typewritten copy or computer printout of digital data. Used to check for errors in typesetting, for example.

Hard disk

A rigid disk sealed inside an airtight transport mechanism. Information stored may be accessed more rapidly than on floppy disks and far greater amounts of data may be stored. Often referred to as Winchester disks.

Hard dot

A very clean, fringe less, sharp dot.

Hardback

A case bound book with a separate stiff board cover.

Hardness

Degree of hardness. Shore and Rockwell being two scales used to measure and compare hardness.

Hardwood Pulp

Pulp made from deciduous trees (trees that drop their leaves, such as maple and oak). Hardwood pulp has short fibers, which give paper bulk, body, and smoothness. Papers are often made from a blend of hardwood and softwood pulps, combining the qualities of both into a single paper.

Head

The margin at the top of a page.

Head trim

Standard allowance (usually 1/8 inch or 3mm) between the tops of pages that are trimmed off.

Headbox

The compartment that holds pulp slurry before it is sprayed or poured onto the paper-forming wire of a papermaking machine.

Header.

See Running head.

Headline

Title of the book at the top of each page of text. When the title is on the verso page and the chapter on the recto it is a running head.

Heat resistance

Property of a material that inhibits the occurrence of physical or chemical changes caused by exposure to high temperatures.

Heat seal

(Heat Activated Labels): Label paper that has a plastic coating that melts under heat to form the bonding agent.

Heat-set inks

Inks that are dried quickly with heat and then chilled.

Heavy coat weight

A higher-than-standard weight of coating per unit area.

Heidelberg

An automatic press first made in 1914 by Schnellpressenfabrik A.G.

Helvetica

A sans serif typeface.

Hemp

A plant fiber used to make paper. Desirable because it grows quickly and its fibers are strong (they are also used to make rope).

Hexachrome

A proprietary colour separation process, developed by Pantone, which uses six (6) instead of four process colours.

Hickeys

An irregularity in the ink coverage of a printed area. Hickeys are caused by paper or pressroom dust, dirt, or pick out on the printing blanket, all of which prevents the ink from adhering to the paper surface aka donut, fisheye, bull’s-eye.

High contrast

Large difference of dark to light areas in a photographic reproduction.

High Temperature Adhesive

An adhesive that will enable a pressure-sensitive label to adhere or stick well when applied to a hot substrate and has a high degree of resistance to aging or deterioration at elevated temperatures.

Highlight

The lightest area in a photograph or illustration.

Holdout

Property of paper that makes it resistant to absorption of ink.

Hologram

Laser-created, three-dimensional recording of a 3D or 2D image reproduced by hot foil stamping or embossing onto reflective- backed mylar.

Home page

The first screen that visitors encounter when they reach a Web site. It typically contains a short introduction describing the purpose of the Web site or the company, association or individual's area of expertise with links that will take visitor to other areas of the site.

Hosting

The maintenance of a computer system and applications at a third-party site.

Hot Melt Adhesive

A pressure-sensitive adhesive applied to the liner or backing in a hot molten form that cools to form a conventional pressure-sensitive adhesive. Thermoplastic materials with 100% solids that liquefy when heated and re-solidify on cooling.

Hot metal

Generic term for type cast from molten metal.

Hot Stamping

A decorating process in which the desired image is transferred to a substrate by a heated, positive copy die. Images are normally limited to one colour positive copy line.

House style

Style of preferred spelling, punctuation, spacing, hyphenation and indentation used by a designer, printer, publishing house or by a particular publication to ensure consistent typesetting.

HTML

Hypertext Markup Language is the language that browsers use to construct a Web page on a computer screen - it is a programming code consisting of symbols - tags - inserted before and after text and the filenames of graphics that are downloaded.

HTTP

Hypertext Transfer Protocaol; request-response protocol, the language spoken between the browser (client software) and the web server (server software) so they can communicate with each other and exchange files.

Hue

Unique distinguishing characteristics between colours as identified by name - for example cyan, magenta, red, blue, or green - as distinct from their brightness or saturation.

Hydropulper

Hydropulper equipment used to slurry pulp. Water is added to dry pulp and fillers, and agitated until the mixture becomes about the consistency of oatmeal cereal.

Hypertext links

A link that permits you jump to areas on the same page, different pages in the same site or a different site by clicking on a word or graphic.

Hyphenation

Breaking of words into syllables separated by hyphens. Impedes readability but is usually necessary to maintain even right margins and text colour in fully justified type.