Typography Definitions
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| Abrupt Serif | A serif which breaks suddenly from the stem at an angle. |
| Accent | A diacritical mark near or through a letter indicating a variation in pronunciation. Eg. ç, à, ò, é, Å. |
| Adnate Serif | A serif which flows smoothly to or from the stem. |
| Aliasing | Distortion due to undersampling (sampling at less than double the highest spatial frequency in the original). Aliasing distorts letterforms and letter spacing. |
| Alphabet | A standard set of written symbols employed in a particular writing system in which the symbols represent phonemes (basic significant sounds) of the spoken language. |
| Analog Letterform | A glyph, drawn or printed, used as a model for creating a digital version. Analog letterform designs maybe expressed as smooth curves that are then digitized. |
| Analphabetic | A typographical character used with the alphabet but lacking a place in the alphabetical order. Examples: the acute accent, the umlaut, the circumflex, and the asterisk. |
| Anisotropic Scaling | Enlarging or shrinking letters nonlinearly, so that, for example, they become disproportionately less bold and narrower for ther height as they are enlarged. Used to adapt typefaces to reproduction at different font sizes. |
| Anti-aliasing | Removing alias frequencies from the sampled signal. It is the addition of controlled amounts of "blur" through a well-defined mathematical formula. |
| Antiqua | Another way to describe letters with serifs. |
| Arc | Segment of a circle or ellipse. |
| Ascender | That part of a lowercase letter that rises above the x-height, as in letters 'b', 'd', 'f', 'h', 'k', 't' and 'l'. |
| ASCII | The American Standard Code for Information Interchange, a standard character set defined by ANSI, the American National Standards Institute. |
| Aspect Ratio | The ratio of width to height. |
| Assimilation | The symmetry propert possessed in varying degrees by a typeface that creates mirror relationships and other similarities of form between letters. |
| Asymmetry | Aspects of letterforms that depart from mirror images relationships between letter pairs, especially 'b-d' and 'p-q', and within individual letters, such as 'T' in some typefaces. |
| Axis | The real or imaginary straight line on which a letterform rotates. |
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| Back Up | To match the vertical position of lines on the opposite sides of a sheet printed on both sides. |
| Ball Terminal | A circular form at the end of the arm in letters such as a, c, f, j, r, and y. |
| Baseline | The line on which letterforms rest. (Round letters like "e" and "o" normally dent it, pointed letters like "v" and "w" normally pierce it, and letters with foot serifs like "h" and "l" usually rest precisely upon it.) |
| Beak Terminal | A sharp spur, found particularly on the f, and also often on a, c, j, r, and y in many 20th century Romans. (Examples: Perpetua, Pontifex, Ignatius.) |
| Bézier Splines | A class of third-degree interpolating splines useful for representing letterform shapes. |
| Bicameral | A bicameral alphabet has two alphabets joined. The Latin alphabet, which you are reading, is an example; it has an uppercase and lowercase. Unicameral alphabets (the Arabic and Hebrew alphabets) only have one case. |
| Bitmap | The mapping of analog data to bits, that is, values which are zero or one. In imaging a bitmap is a way to store a binary image, that is, an image in which each pixel is either black or white (or any two colors). |
| Bitmapped Display | An output device that portrays a bitmap image. A raster display is a bitmap display in which the bitmap data are scanned line by line. |
| Blackletter | A general name for a wide variety of letterforms that stem from the north of Europe. Blackletters are generally tall, narrow, and pointed. In architecture, comparable to the gothic style. |
| Blackness | The apparent darkness of type as it appears on the page. Blackness depends on the boardness of the parts of the letter (boldness), as well as on the x-height and set. |
| Bleed | An image that extends to the edge of the paper (after trimming). |
| Bodoni | A modern typeface with unbracketed serifs, veritcal stress and very high contrast. |
| Body Size | The height of the face of the type. Originally, this meant the height of the face of the metal block on which each individual letter was cast. In digital type, it is the height of its imaginary equivalent, the rectangle defining the space owned by a given letter (different from the dimension of the letter itself). |
| Bold | A blacker, heavier variation of a typeface, relative to the roman variation. |
| Bowl | The generally round or elliptical forms which are the basic body shape of letters such as (uppercase) C, G, O, and (lowercase) b, c, e, o, and p. Similar to the space known as an "eye". |
| Break | A non-printing instruction in typesetting and page layout used to start a new line, column or page. |
| Brightness | The perceived intensity level of light in a visual scene. |
| Brilliance | Property of a typeface related to its typographic contrast. Also referred to as sparkle. |
| Bullet | A mark used to set off items in a list, frequently a filled circle. |
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| Calligraphic Display | An image-display device that produces images by directly creating lines, arcs, and so on, as opposed to a bitmap display. Also called a stroke display. |
| Cap Height | The distance from baseline to cap line of an alphabet, which is the approximate height of the uppercase letters. It is often less, but sometimes greater, than the height of the ascending lowercase letters. |
| Cedilla Ç | The accent, used primarily in French, to soften the letter C. |
| Cell Text | A monospaced typeface, usually associated with older display devices. |
| Centered | Text set so as to distribute residual space on the line equally to the right and left. |
| Character | An abstract symbol, represend within a computer by a numerical code. Also, a symbol in a font or glyph. |
| Character Set | An ordered set of abstract symbols, used ti represent and exchange information, in which a paricular symbol is represented by its index. |
| Chase | Rectangular frame used to lock lines of metal type into position in letterpress use. |
| Cicero | A unit of measurement used to measure typefaces. It is equal to 12 Didot points, the slightly larger continental European counterpart to the American and British point. |
| Classical Type Style | Letterforms having vertical axis, adnate serifs, teardrop terminals and moderate aperture. Originated in the 18th century. |
| Colophon | A description of how a book was produced, normally at the end. Also, a printers' mark or emblem. |
| Color (in typography) | The overall blackness of a page of text, that is, its average density. By extersion, the blackness of a typeface when set in a block. |
| Compound Document | A document that contains, in addition to text, graphics, images, or other non-textual components |
| Condensed | A type design variation with less than normal set; thus a tightly spaced font. |
| Conic Spline | A spline curve of order two. |
| Contrast (in typography) | The ratio of thickness of vertical to horizontal strokes in letterforms. |
| Counter | The white space enclosed by a letterform, whether wholly enclosed (as in "d" or "o") or partially (as in "c" or "m"). |
| Cubic Splines | A spline curve of order three. |
| Cursive | Typefaces that resemble handwriting, frequently having joins or the suggestion of joins between letters. |
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| DDL | A page-description language developed by Imagen Corporation. |
| Decode | In reading, to identify letters and words. |
| Demerits | A point system used to rate the quality of a particular arrangement of type, for example, when line breaking in TEX. Lines receive demerits for faults such as being too loose or tight; paragraphs, for defects such as consecutive hyphenations. |
| Dentation | The vertical extent on the page of a block of print. |
| Descender | That portion of a letter that falls below the baseline, as in 'j', 'g', 'q', 'p' and 'y'. |
| Desktop Publishing | Direct design and printing of typeset material using small, relatively inexpensive computers and printers under the direct control of the creator of the material. |
| Diacritical mark | An accent or other ancillary mark added to a letter to distinguish it or change its pronunciation. |
| Diaresis | The accent used to separate the pronunciation of two consecutive vowels, as in coördinating. Similar to the umlaut |
| Didot point | Unit of type measurement in Europe (not Britain) 1 Didot point = 0.3759 mm. |
| Digital halftoning | The simulation of continuous-tone pictures by the algorithmic arrangement of bivalued picture elements. Also called spatial dithering. |
| Digital typography | The technology of using computers for the presentation of text, in which the letters themselves are created and positioned under digital control. |
| Digitisation error | The loss of information in the sampling of a signal. The broader class of errors of which aliasing is an example. |
| Digitise | To sample an analogue signal and represent the results in a numeric form. |
| Dingbat | A special symbol not a part of any particular typeface, including arrows, mathematical signs such as square root, and bullets. |
| Display (typography) | Large sizes of type, for use as headlines, titles, and so forth. |
| Display Type | General term for type set larger than surrounding text as in headings or advertisements. Usually 14-point or larger. |
| Displayed formulas | Sequences of lines of mathematical notation included within running text. |
| Dithering | Spatial dithering, the method of creating digital halftones. |
| Document model | An external system that presents textual and graphical information as (simulated) paper documents. |
| Document | Any "printed" image stored in a computer or realised on a piece of paper. |
| Dots per inch (dpi) | Measure of the resolution of input and output devices. |
| Double Storey | Seen in the lower case "g" with the closed tail and lower case upright finial "a". |
| Draft printing | Printing a test copy of a document, usually in low resolution or print quality, before printing it in final form. |
| Drop Cap | A large initial capital in a paragraph that extends through several lines. |
| Drop Folio | A folio (page number) dropped to the foot of the page when the folios on other pages are carried at the top. Drop folios are often used on chapter openings. |
| Dyslexia | A perceptual aberration, one form of which causes confusion of mirror-image letter pairs, especially 'p-q' and 'b-d'. |
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| Edge enhancement (image processing) | An image-processing technique that identifies the boundaries of objects and increases their contrast. |
| Egyptian Type | Letterforms having square serifs and almost uniform thickness of strokes. |
| Electrographic printer | A printer that uses a direct electrostaticprinting process in which charge is placed directly on the paper and then developed to form an image by the application of toner. |
| Electronic publishing | Digital typography. |
| Elite | A typewriter (monospaced) typeface with a pitch of 12 char, acters per inch. |
| Em Space | An amount of space that can either the width of an uppercase "M" or the actual body size of a given font (sometimes both definitions are the same). Also known as a "mutton". |
| Emdash | A dash the width of the letter "m" used in text to separate a parenthetical note as an alternate to parenthesis. |
| En space | Half an em. Also known as a "nut". |
| Endnote | A piece of text associated with the body of a document, like a foot-note but placed at the end of a section or chapter. |
| Erosion | The thinning of the vertical strokes in letter forms that results from characteristics of the output device. |
| Expanded | A type design variation with more than normal set. Thus, a loosely spaced or wider than normal font. |
| Extender | Descenders and ascender; i.e., the parts of the letterform that extend below the baseline (p, q) or above it (b, d). |
| Extensional specification | In a document formatter, the detailed specification of formatting information such as spacing, margins, and font, as opposed to intentional specification, in which the purpose of a passage is described, for example, verse. |
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| Facsimile | Electronic representation of images, often entire documents, for transmission over a distance, frequently by a telephone or computer network using digital encoding. |
| Family | A related set of typefaces or fonts. |
| Figure (perception) | The object seen, as separated in the act of seeing from everything else in the image. |
| Figure (typography) | A picture or diagram that may be included within the body of a typeset document. |
| Figures (lining) | Modern numbers, all of which rest on the baseline and are equal in width (so that vertical columns line up). |
| Figures (nonlining) | Old-styled numbers, some of which (3,4,5,7,9) descend below the baseline. |
| Fill | The graphical operation of reproducing a pattern or color through, out a bounded area. |
| Fixation | The stopping of the eye to sample the visual scene. Even during fixations, there are continual small motions of the eye. |
| Fixed pitch | Monospaced type |
| Fleuron | A printer's flower or ornament. |
| Flicker fusion frequency | The temporal rate of intensity variation of alight or image at which a particular person sees the light as steady. Flicker-fusion frequency varies from person to person, with the degree of modulation of the intensity variation, and with the angle from the centre of the visual field. |
| Floating object | An illustration, table, or diagram that the document formatter is free to place in various places relative to the running text. |
| Flower | A printer's decorative symbol. Also called a fleuron. |
| Flush left | Setting lines of text so that any extra space is on the right, and the text is against the left margin. Also called ragged right. |
| Flush right | Setting lines of text so that any extra space is on the left, and the text is against the right margin. |
| Folio | A page number, for example as part of a running head or foot. |
| Font | A set of characters. In the world of metal type, this means a given alphabet, with all its accessory characters, in a given size. In digital typography, it is the character set itself or the digital information encoding it and is independent of size. |
| Footnote | A floating note associated with a location and reference mark in a text and displayed at the bottom of the page on which the mark occurs. |
| Foreground | The image or figure, as opposed to the background. |
| Foundry | Originally, a factory in which metal type is made; now any maker of type. |
| Fovea | In the eye, the small, central region of the retina that exhibits the greatest sensitivity to detail and color. |
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| Galley | In traditional typesetting, a proof of the running text, tables, or figures, before these parts are combined to form pages. |
| Gestalt | The perceptual process of separating figure and ground to create an overall visual understanding of an image. |
| Glyph | (1) The actual shape (bit pattern, outline) of a character image. For example, an italic 'a' and a roman 'a' are two different glyphs representing the same underlying character. In this strict sense, any two images which differ in shape constitute different glyphs. In this usage, "glyph" is a synonym for "character image", or simply "image".
(2) A kind of idealized surface form derived from some combination of underlying characters in some specific context, rather than an actual character image. In this broad usage, two images would constitute the same glyph whenever they have essentially the same topology (as in oblique 'a' and roman 'a'), but different glyphs when one is written with a hooked top and the other without (the way one prints an 'a' by hand). In this usage, "glyph" is a synonym for "glyph type", where glyph is defined as in sense 1. |
| Greyscale fonts | Fonts that use variations in intensity at the edges of the letters to suppress the effects of aliasing and thus improve the apparent sharpness and fineness of letterforms. |
| Greeking | The use of gray bars or "dummy" characters to represent text that is too small to be legible when displayed on the screen. Also, in graphic design, the use of dummy text in a layout so that the design of the document will be emphasized rather than its content. |
| Grid (typography) | A graphical layout for the design of pages of a book or other document. Variations on pages must match divisions in the grid. |
| Grotesk | Another way to describe letters without serifs. |
| Ground (perception) | That part of an image that is seen as the background, rather than the perceived object, called the figure. |
| Gutenberg: unit of measure | A unit of linear measure equal to 1/7200 inch, or about 1/100 of a point. |
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| H and J | Also H/J. Typesetting abbreviation for hyphenation and justification. |
| Hairline | The thinnest part of a letter other than the serif. Joins are frequently hairlines. Also, a fine line or rule, the thinnest that can be reproduced in printing. |
| Half-bitting | The manipulation of the edges of graphic images so as to minimise the effects of aliasing and reconstruction errors. Also called dentation. |
| Half tone | A method of simulating continuous-tone images with a device that has a small number of output tones, colors, or intensities. The patterns used are called dithers |
| Heading | Text that introduces sections of text, set off from the text by differences in size, typeface, or position. |
| Helvetica | A popular sans serif typeface. |
| Hershey fonts | A public-domain set of typefaces specified as strokes, originally for pen-and-ink plotters, still used in rasterized bitmap form. |
| Hinting (font hinting) | The use of mathematical instructions to adjust the display of a vector font so that it is most clearly displayed in rasterized form. At low screen resolutions (and small print sizes) hinting is critical for producing clear, legible text. It can be accompanied by antialiasing. |
| Humanist Type Style | Letterforms which originate from the humanists of the Italian Renaissance. Based (generally) on letterforms as they might be written by hand. |
| Hypertext | A system proposed by Tim Berners-Lee and others in which a rich structure of interconnections is created and used within on-line electronic documents. e.g. the World Wide Web |
| Hyphenation | The splitting of a word across lines as an aid to uniform line breaking. |
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| Illusions | Perceptions created in the visual system and brain that differ from the "objective" environment as determined by physical measurements. |
| Image contrast | The ratio of the maximum luminance (intensity) in an image to the minimum luminance. Also called Dynamic Range. |
| Imposition | In printing, the arranging of pages on a larger sheet in the correct order and orientation so that when the sheet is folded the pages will appear in order. |
| Indentation | Insetting a line of text in from the margin, as at the beginning of a paragraph or within an outline, or to set off a quotation. |
| Inline font specification | A pen path that, in conjunction with a pen shape for marking along the path, specifies a letterform. |
| Intensity | The luminance of light. |
| Intentional specification | In a document formatter, the functional specification of formatting information without providing details of spacing, margins, font, or the like, as opposed to extensional specification, in which detailed formatting changes are described. |
| Interlaced display | A technique used with CRT displays to reduce the data rate at which the display must be refreshed. Two fields, containing alternate lines, are refreshed alternately. |
| Interletter space | The horizontal space between individual letterforms within a single word. Interletter space may be adjusted as a function of the letters (see kerning), but its proper value is an integral part of the typeface design. |
| International Typographic Style | Typographers and designers who based their designs on mathematical grids. ITS felt that the san serif type faces were the thing of the future. |
| Interpolating curves | Parametric curves that are constrained to pass through the control points that specify them. |
| Interword space | The horizontal space between words on a line. Interword space can be adjusted to achieve justification. |
| ISO | International Organization for Standardization, headquartered in Geneva. An agency for international cooperation on industrial and scientific standards. |
| Italic | A type design that is both slanted and script like cursive. It was originally designed to replicate handwriting. |
| ITC | International Typeface Corporation, a major vendor of typefaces. |
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| Jaggies | The stepped effect of bit-mapped type and graphics caused when square pixels represent diagonal or curved lines. |
| Joint | The point in common between two adjoining segments of a spline curve. |
| Justification | Generically, placing lines of text in a particular relationship to one or both margins. As distinct from flush left or flush right, justified text has both the left and right margins even. |
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| Kern (n.) | Part of a letter that extends into the space of another. |
| Kern (v.) | To alter the fit of specific letter combinations so that the limb of one projects over or under the body or limb of another. |
| Knot | The point where connected curves join. |
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| Landscape orientation | A layout wider than it is high, whether on screen or paper. |
| Laser printer | A device similar to an office copier in which the image is created on a photosensitive surface, usually a drum, via a computer-controlled beam of light from a laser. |
| Lateral inhibition | The basic means by which edges are detected in the retina. Adjacent excitatory and inhibitory regions signal differences in illumination between them. |
| LCD | Liquid Crystal Display. |
| Leading | Originally a horizontal strip of soft metal used for vertical spacing between lines of type. Now meaning the vertical distance from the baseline of one line to the baseline of the next. |
| Left justify | Setting text against the left margin, that is, with unused space all placed at the right. Also called ragged right. |
| Legibility | The ease with which text is read in ordinary, continuous reading, usually gauged by reading speed and error rate. Also, Readability. |
| Letterform | A single glyph or letter, such as might be found on a page or screen. Also, the design of such a letter. |
| Letterpress | Traditional method of relief printing in which individual pieces of type, called sorts, are assembled from cases into lines and blocks of text and printed by inking and direct contact with paper. |
| Letterspacing | Adjustment of the interletter space within words so as to achieve equal optical space, or sometimes line justification. Also called "Tracking". |
| Ligature | Two or more letters tied into a single character to perfectly design their spatial interaction. |
| Lines per inch (LPI) | The spatial resolution of a device, photographic emulsion, and so forth, expressed as the greatest number of parallel lines per inch that can be resolved. Related only indirectly to dots per inch, which specifies addressing resolution, but not the greatest number of lines that can be sensed or created, which will be at least two times smaller. |
| Linotype, or LT | A typesetting machine, invented in 1886 by Ottmar Mergenthaler, that casts slugs containing whole lines of type for relief printing. |
| Liquid crystal display (LCD) | A screen-display technology that uses optically active organic materials to selectively reflect light under electronic control. |
| Logotype | A typographic trademark or symbol, frequently using distorted letterforms. See advice on Logotype design. |
| Loose line | A line of print that contains too much blank space (normally between words) compared with adjacent lines and general norms. The nominal interword space used in conventional printing is between a quarter and a third of the point size. |
| Low-pass filter | A filter that allows low frequencies through, but eliminates high frequency components. |
| Lowercase | Small letters used in printing that evolved from the Caroline minuscules originating around the year 800 CE. So called because they are found in the lower part of the printer's type case. |
| Lucida | A typeface designed by Bigelow & Holmes specifically for digital output. Its low-resolution screen version is known as Pellucida. |
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| Macros | Open subroutines, often used to create new commands. |
| Majuscule | A capital (or other large) letter. |
| Margin | The blank space to the left, right, above, and below the text on a page. Margins may contain up to 50% of the area of a well-designed book page. |
| Marginalia | Notes, titles, summaries, or other information in the margins of a document. |
| Matrix | The copper block onto which the steel die for a letter was stamped. The matrix served as the mold for the face of a type or for a printing plate. |
| Markup language | A formatting language, that includes textual instructions to the formatter, intermingled with the text to be formatted. For example, HTML & LaTeX. |
| Mechanical | A camera-ready original, ready for reproduction by off, set printing. |
| METAFONT | Font production language developed by Donald Knuth. |
| Metal type | Typesetting technology prior to phototypesetting, a kind of relief printing. See letterpress, linotype and monotype. |
| Minuscule | Archaic term for a lowercase letter, see also majuscule. |
| Modern Type Style | Letterforms with flat serifs, abrupt and exaggerated strokes, and vertical shading. Originated by Francois Didot in the late 18th century, this style represented a casting away of the decorative baggage of the rococo era. |
| Monochrome | existing entirely in black and white and shades of gray. |
| Monospaced printing | Printing in which each letter or symbol occupies the same horizontal space. |
| Monotype | Typesetting machine invented in 1893 by Tolbert Lanston that casts individual letters and assembles them into a block of type, following instructions punched on a paper tape. |
| Mood of type | The subjective feeling imparted by a typeface, layout, or page of type. |
| Movable type | Johannes Gutenberg's invention: Individual letters cast on independent metal bodies (or cut from wood), for assembly into blocks for printing. |
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| Noise: engineering | That part of a signal, image, and so forth that is independent of the information content of the message. |
| Nroff | The UNIX batch-oriented document formatter, closely associated with troff, which is used for phototypesetting. It has some programming features such as environments. |
| Nyquist frequency | The sampling rate at which sufficient information is captured so as to be able to reproduce a signal of a given bandwidth. The Nyquist frequency is exactly twice the highest frequency to be resolved. |
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| Oblique | A slanted type design, following the letter shapes of the roman variation, as opposed to italic, which is also cursive. |
| ODA | Office Document Architecture, an interchange format for expressing revisable, structured documents, not intended to be human readable. |
| Office typography | The design and printing of documents for everyday business, scientific, professional, and engineering use. Before desktop publishing, a generally haphazard affair. |
| Offset printing | Printing method in which an image is developed on one surface and transferred (offset) onto another, and eventually onto the paper. |
| Oldstyle typeface | A group of typefaces typified by oblique, bracketed serifs. |
| On-Demand publishing | Creation of printed documents in small runs or even in single copies, as needed. |
| Optical spacing | Positioning of letters so that they are perceived as having equal spaces between them. Exact geometric spacing does not have this property. |
| Orphan | A header or the first line of a paragraph that appear as the last line on a page. |
| Outline font description | Specification of the shapes of letters by defining their boundaries (to be filled with the ink color). |
| Overleaf | The other side of a sheet printed on both sides, specifically the page in a book after a right hand page. |
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| Page Description Language (PDL) | An executable description that expresses the appearance of a typeset page or series of pages. DDL, Interpress, and PostScript are examples. |
| Page independence | The property of a page description language that allows the pages within a document to be processed and printed in any order. |
| Pagination | Laying out the parts of a document into pages. |
| Parse | To decode and understand, relative to a grammar. Written and spoken language is parsed in reading or listening. Visual images can also be spoken of in these terms. |
| Pattern recognition | The process of extracting information and structure from a signal or image, by reference to known signals or images. |
| Pel | A picture element or pixel. |
| Perception | Seeing and understanding objects by human beings. |
| Perpetua | Serif typeface designed by English sculptor and typeface designer Eric Gill. |
| Persistence of vision | The property of the visual system that allows a short flash of light or exposure to an image to be perceived over a longer period of time. |
| Photo-offset printing | A printing process in which ink adhering to a photographically processed plate is transferred to paper via one or more intermediate surfaces (rollers). |
| Photocomposition | Typesetting method in which images of letterforms are set by photographically imaging master versions onto film or photographic paper. |
| Phototypesetting | See Photocomposition. |
| Pi font | A font of special symbols not in the standard character set. |
| Pica | A unit of typographic measure, equal to 12 points, or about 1/6 inch. Also, a typewriter (monospaced) typeface with a pitch of 10 characters to the inch and a vertical spacing of six lines per inch (hence the name). |
| Pixel | A picture element, which is also called a pel. The spot of graphical information displayed at a single location on a screen or other output device, or on paper. |
| Plasma display | Screen-display technology that uses ionised gas (plasma) to create an image. In some plasma devices, the light emitted by the plasma is used to stimulate a phosphor, which then emits visible light. |
| Point | A unit of measure used by printers, equal to 1/72 inch. See also Didot point. |
| Point size | The height of a font, expressed in points. |
| Polygons | A straight-line representation sometimes used to express typefaces in outline form. |
| Portrait orientation | A vertical-format page or screen, one higher than it is wide. |
| PostScript | A page-description language developed by Adobe Systems, Inc. |
| Proof | A working copy of typeset material printed for the purpose of checking content and format and of making corrections. |
| Property sheet | A form that describes the formatting characteristics of an object within a WYSIWYG editor/formatter. The sheet is normally hidden, but may be made visible for inspection or modification. |
| Proportional spacing | Printing in which each letter or symbol occupies an amount of horizontal space that depends upon its design. |
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| Quad (printing) | A space equal to the type size. Also, to fill a large blank space in a line with spacing material. |
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| Ragged right | Left-justified text that is flush with the left margin and ragged at the right margin. Unused space in each line is at its right. |
| Random-access display | A display device that draws the image in any specified order. Calligraphic displays are random access. Raster devices are not. |
| Raster device | A device that produces an image by scanning it as a series of lines. |
| Readability | The speed at which continuous text can be read. Also Legibility. |
| Real-time formatting | Presentation of an electronic document in (nearly) printed form while it is being edited. |
| Recto page | Right-hand page in an opening. Has an odd page number. |
| Reference mark | A symbol used to refer the reader to a footnote or other information outside of the immediate context of the mark. |
| Reflection | Light impinging upon a scene that returns back from the scene. Reflections from display screens reduce image quality by reducing contrast. Light reflected from paper (but not the ink) increases image contrast. |
| Refresh | To redisplay information on a display device. CRT displays, for example, refresh the image many times per second to achieve the appearance of constancy. |
| Relief printing | A printing process in which a raised surface accepts ink, which is then transferred to paper by direct contact. |
| Replicating pixels | A method of enlarging an image by mapping each original pixel onto more than one pixel in the enlarged image. Simple transformations like this result in poor-quality enlarged images. |
| Resolution | The fineness of position and detail produced by an output device or sampled by an input device. |
| Retina | The photosensitive part of the eye, upon which the lens images the scene being viewed. river. A perceived white rift in a block of type that results from the alignment of interword spaces from line to line. Proper layout and typesetting minimise or eliminate rivers. |
| Roman | The classical style of type that is upright, as opposed to oblique, is of normal weight as opposed to light or bold, and has graduated thick and thin strokes as opposed to being cursive. |
| Rule | A thin line, either vertical or horizontal, often used to separate parts of a table or columns of text. |
| Run-length encoding | A datacompression technique that represents sequences of values by counts of sequential items of the same value, instead of representing the values individually. |
| Running head | Text such as the title, chapter, or section headings that is repeated on the tops of pages of a book. |
| Runoff | A number of document-formatting programs of related ancestry that operate in batch mode and use a highly extensional set of formatting commands. Macros within Runoff allow more intentional formatting. |
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| Saccade | Motion of the eye between fixations. |
| Sans serif | A typeface without serifs. |
| Saturation | The purity of color; the degree to which light is pastel versus vivid. |
| Script | A form of typeface based on writing, having generally continuous strokes that connect letters. |
| Sector kerning | One method of automatic kerning that calculates the interletter spacing based on stored information about the lateral extent of each letter, assessed in a number of horizontal bands. |
| Selection | The user-interface action of identifying an object or a portion of text for later operations. |
| Serif | A small stroke at the end of the main strokes of letterforms. Typefaces with serifs are called serif typefaces and those without, sans serif typefaces. |
| Set or Set Width | The horizontal extent of a given letter. Also, the average width of the letters in a font, normally gauged by the width of a lowercase alphabet. |
| SGML | Standard Generalised Markup Language, an ISO standard revisable document format. |
| Shoulder | In letterpress type, the level of metal upon which the relief letter sits on a piece of type. The shoulder provides support in letterpress printing for kerns that project from adjacent pieces. |
| Sidebearings | The spaces at the left and right of each letter in a font design that allow for the normal spacing of the letters. |
| Signature printing | Books, magazines, pamphlets, and the like are often printed in signatures, large sheets of paper that are folded, bound, and trimmed to form the finished product. The pages must be printed out of order, half of them upside down, and on both sides, for the pages in the folded sheet to be in the right order and orientation. |
| Simultaneous contrast | An illusion in vision in which equal light intensities appear different as a result of differing surrounding intensities. |
| Size of type | The distance between adjacent lines of type with no extra space (leading) added between them. The type design determines how much of this overall space is actually occupied by letters when printed. |
| Smoothing | An interpolation technique that attempts to remove jaggedness from bitmap images, which may be useful, for example, when screen bitmaps are printed at higher resolution. |
| Sort | A piece of metal type. |
| Space | The part of the printed page that is not occupied by print or other images. The ground or complement of the image. |
| Sparkle | A typographic property associated with many classical, readable typefaces that is related to their typographic contrast. |
| Spatial dithering | The method of creating halftones digitally using a bitonal output device. |
| Spatial frequencies | The analysis of print or other images in terms of rate of variation of intensity over distance. |
| Spline | A mathematical curve specified by a number of points and possibly tangents. Also, a drafting tool for drawing such curves. |
| Spot size | The dimension of the region illuminated by the electron beam in a CRT. Since the spot has soft edges, the spot size is measured between the 50% luminance points. |
| Spread | The broadening of letter features because of the spreading of ink in the printing process. For example, letters are broadened when printed through a cloth ribbon. stem. A main (vertical) stroke in a letterform. |
| Stroke display | An image display device that produces images by directly creating lines, arcs, and so forth, as opposed to a bitmap display. Also called a calligraphic display. |
| Stroke font | Letterforms defined by pen (or beam) paths rather than by outline or raster. |
| Subpixel addressing | The positioning of glyphs on a grid effectively finer than the pixel resolution of the output device, using greyscale. |
| Subscript | Letters or symbols positioned slightly below the baseline within a line of text and generally smaller in size. |
| Swash letters | Fancy alternative decorative letters, usually available only in italic capitals. |
| Symbol | Any graphic form such as a letter, number, punctuation mark, or mathematical sign. |
| Symmetry | The property of similarity within a letterform or between letterforms of the same design. For example, the letter 'T' in some typeface designs has right-left mirror symmetry, but does not in other faces. |
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| Tables | Rectangular arrangements of text, numbers, or other textual information. Tables generally float in documents, and may be positioned in a number of places relative to the text that refers to them. |
| Tangent | The direction of a curve; also, specified point; also, a line through this point and oriented in this direction. |
| Text | Any sequence of graphic symbols. |
| Texture (typography) | The appearance of a page or block of text, perceived as a surface. |
| TITLE | A popular contemporary serif typeface originally developed by Stanley Morison for the London Times. It has a relatively large x-height, and is relatively narrow (small set) for its x-height. |
| Toner | The ink used by laser printers and photocopiers. |
| Type | Originally metal type, now a typeface design or some typeset text. |
| Typeface | A distinctive, visually consistent design for the symbols in an alphabet. |
| Typesetter | A machine for setting type. Professional digital typesetters that output on photographic paper have printing resolutions between about 700 and 5000 dpi. |
| Type size | The size of a typeface, measured from line to line, when no additional interline space is added. Digital typefaces may not have an inherent size, as did metal typefaces. |
| Typewriter fonts | Usually monospaced typefaces, in the style of traditional typewriter typefaces, now used to indicate computer printout or a typewritten style of document. |
| Typographer | A professional designer of type, books, magazines, and other printed matter. |
| Typography | The art and practice of designing type, books and other printed matter according to aesthetic and scientific principles. |
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| Uppercase | A capital letter, so called because of the placement of capital letters in a printer's type case. |
| Uncial | Uncial (pronounced un:shel) is a term applied to a particular calligraphic style based on ancient lettering, and is often considered the most expressive calligraphy. Typically an uncial face features a combination of capital and lowercase letterforms without the separate capital set and lowercase set that we're accustomed to. |
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| Verso page | Left-hand page of an opening. It has an even page number. |
| Visibility | The degree to which letters or words can be identified and discriminated, without regard to the speed of reading. |
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| Weight | Heaviness or blackness of a font or letters. Numerically, the ratio of the widths of vertical strokes to the x-height. |
| Widow | The last line of a paragraph that appears at the top of a page. |
| Winding number | A method of determining whether a region is inside a curve, and thus should be inked when an outline-specified letterform is rasterized. |
| Word processing | Preparation of text in document form. The term is now dated, suggesting text-only documents and impact printing, as opposed to typeset compound documents. |
| WYSIWYG | Acronym for What You See Is What You Get, used to describe interactive editing or formatting in which a facsimile of the paper output is presented on the screen, coined by Doug Engelbart. |
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| X-Height | The height of a lowercase letter 'x' in a particular font. |