Hairline:

A very thin line or gap about the width of a hair or 1/100 inch.

Hairline Rules:

The thinnest rule that can be printed.

Halftones:

The printed reproduction of a photograph (black and white or colour) reproduced by the positioning of a halftone screen (see reproduction, plate making and proofing) on the original. A way of converting (rasterising) a greyscale or colour image (e.g. a photograph) into a pattern of dots for output on a printer or image-setter. Halftones can be positive or negative and on film or paper.

Halftone Dot:

Basic unit of a halftone screen. Gray level in a black and white halftone is determined by the size of a halftone dot. A halftone dot generated by digital methods may consist of one to 500 or more pixels whose number is dependent on the resolution of the output device, and the screen ruling of the halftone.

Halftone Screen:

A type of screen, either optical (in a process camera) or electronic (in a scanner) that is used to convert the original continuous tone image into a pattern of dots on film. This screen, which works like a fine grid, converts the continuous tones to dots whose sizes vary depending on the tonal value of the original.

Handshaking:

The process computers and modems go through in order to establish a connection and "agree" on the speed and protocols for data transmission.

Hardback:

A case bound book with a separate stiff board cover.

Hard Copy:

The permanent visual record of the output of a computer or printer. The typed text sent to a typesetter for conversion into typeset copy. The printed version of the document created on the computer. It may be printed onto paper, film or any other permanent article.

Hard Temper Foil:

Foil fully work-hardened by rolling.

Hardware:

The parts of your computer system that you can touch, feel and taste -hard disks, printers, modems, scanners, cards, keyboards, the mouse and the computer itself.

Hatching:

An area on the form that is printed with a pattern, usually jumbled letter or numbers that obscures any image that has been printed through a multi part form.

Head:

The margin at the top of a page.

Heat Seal Coating:

A coating on a material, which allows that material to be laminated to a second material with a surface that when heat is applied the two materials will bond together. The bond strength is such that the materials will be destructed if one tries to peel apart the two. Also called a destruct bond.

Hexacrome:

Four colour process plus orange and green.

Hickey:

A doughnut-shaped spot or imperfection in printing, most visible in areas of heavy ink coverage. Any spots or specks due to dirt on the pages, dried ink skin, paper particles, etc.

High-Bulk Paper:

A paper made thicker than its standard basis weight.

Highlight:

The lightest areas in a photograph or halftone.

Hot Melt:

Type of adhesive which becomes liquid at high temperatures, and immediately reverts to the solid state at normal temperature.

Hot Tack:

The ability of a freshly made seal to resist puckering, or separating when stressed.

H.S.W.O. -Heat Set Web Offset:

A rotary printing process using heat to set the ink. A cylinder transferring the image from the printing plate to blanket to paper at speeds of 30000 or more impressions per hour.

Hue:

The colour of an object perceived by the eye due to the fact that a single or pair of RGB primary colours predominates.