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41 <h1 id="terms" class="docs">Definitions of terms used in this manual</h1>
44 I use a number of typesetting-specific and groff-specific terms
45 throughout this documentation, as well as a few terms that apply
46 to mom herself. To make life easier, I’ll explain
47 them here. Refer back to this section should you encounter a word
48 or concept you’re not familiar with.
51 <div class="rule-short" style="margin-top: 18px; margin-bottom: 28px;"><hr/></div>
53 <div class="col-1-definitions">
54 <table class="definitions">
55 <tr><th class="definitions">Typesetting terms</th></tr>
58 <a href="#ascender">Ascender</a><br/>
59 <a href="#baseline">Baseline</a><br/>
60 <a href="#ballotbox">Ballot box</a><br/>
61 <a href="#bullet">Bullet</a><br/>
62 <a href="#capheight">Cap-height</a><br/>
63 <a href="#descender">Descender</a><br/>
64 <a href="#discretionaryhyphen">Discretionary hyphen</a><br/>
65 <a href="#dropcap">Drop cap</a><br/>
66 <a href="#em">Em/en</a><br/>
67 <a href="#family">Family</a><br/>
68 <a href="#figurespace">Figure space/Digit space</a><br/>
69 <a href="#fixedwidthfont">Fixed width font</a><br/>
70 <a href="#fixedwidthspace">Fixed width space</a><br/>
71 <a href="#font">Font</a><br/>
72 <a href="#force">Force justify</a><br/>
73 <a href="#just">Justify/justification</a><br/>
74 <a href="#gutter">Gutter</a><br/>
75 <a href="#kern">Kerning</a><br/>
76 <a href="#kernunit">Kern Units</a><br/>
77 <a href="#leading">Lead/leading</a><br/>
78 <a href="#leader">Leaders</a><br/>
79 <a href="#ligatures">Ligature</a><br/>
80 <a href="#picaspoints">Picas/Points</a><br/>
81 <a href="#ps">Point Size</a><br/>
82 <a href="#quad">Quad</a><br/>
83 <a href="#rag">Rag</a><br/>
84 <a href="#shape">Shape</a><br/>
85 <a href="#solid">Solid/set solid</a><br/>
86 <a href="#trackkerning">Track kerning/Line kerning</a><br/>
87 <a href="#unbreakablespace">Unbreakable space</a><br/>
88 <a href="#weight">Weight</a><br/>
89 <a href="#wordspace">Word space</a><br/>
90 <a href="#xheight">x-height</a><br/>
96 <div class="col-2-definitions">
97 <table class="definitions">
98 <tr><th class="definitions">Groff terms</th></tr>
101 <a href="#alias">Alias</a><br/>
102 <a href="#arguments">Arguments</a><br/>
103 <a href="#commentlines">Comment lines</a><br/>
104 <a href="#controllines">Control Lines</a><br/>
105 <a href="#filled">Filled lines</a><br/>
106 <a href="#inlines">Inline escapes</a><br/>
107 <a href="#inputline">Input line</a><br/>
108 <a href="#macros">Macros</a><br/>
109 <a href="#units">Machine units</a><br/>
110 <a href="#numericargument">Numeric argument</a><br/>
111 <a href="#outputline">Output line</a><br/>
112 <a href="#primitives">Primitives</a><br/>
113 <a href="#stringargument">String Argument</a><br/>
114 <a href="#unitofmeasure">Unit of measure</a><br/>
115 <a href="#zerowidthcharacter">Zero-width character</a><br/>
121 <div class="col-3-definitions">
122 <table class="definitions">
123 <tr><th class="definitions">Mom terms</th></tr>
126 <a href="#blockquote">Blockquote</a><br/>
127 <a href="#controlmacro">Control macro</a><br/>
128 <a href="#docheader">Docheader</a><br/>
129 <a href="#epigraph">Epigraph</a><br/>
130 <a href="#footer">Footer</a><br/>
131 <a href="#head">Head</a><br/>
132 <a href="#header">Header</a><br/>
133 <a href="#linebreak">Linebreak</a><br/>
134 <a href="#parahead">Paragraph head</a><br/>
135 <a href="#pdflink">PDF link</a><br/>
136 <a href="#pdfoutline">PDF outline</a><br/>
137 <a href="#quote">Quote</a><br/>
138 <a href="#running">Running text</a><br/>
139 <a href="#toggle">Toggle</a><br/>
145 <h3 id="typesetting-terms" class="docs">Typesetting terms</h3>
147 <dt id="ascender">Ascender</dt>
149 The portion of a letter that extends above the bowl. For
150 example, the letters a, c, and e have no ascenders. The letters
154 <dt id="baseline">Baseline</dt>
156 The imaginary line on which the bottoms of capital letters and
157 the bowls of lower case letters rest.
160 <dt id="ballotbox">Ballot box</dt>
162 An unfilled square, usually
163 <a href="#capheight">cap-height</a>
164 in size, typically placed beside items in a checklist.
167 <dt id="bullet">Bullet</dt>
169 A small, filled circle typically found beside items or points in
173 <dt id="capheight">Cap-height</dt>
175 The height of the tallest capital letter in a given
176 <a href="#font">font</a>
178 <a href="#ps">point size</a>.
181 <dt id="descender">Descender</dt>
183 The portion of a letter that extends beneath the
184 <a href="#baseline">baseline</a>
185 (j, q, y are letters with descenders).
188 <dt id="discretionaryhyphen">Discretionary hyphen</dt>
190 A symbol inserted between two syllables of a word that indicates
191 to a typesetting program the valid hyphenation points in the
192 word. Normally, if hyphenation is turned on, groff knows where
193 to hyphenate words. However, hyphenation being what it is
194 (in English, at any rate), groff doesn’t always get it right.
195 Discretionary hyphens make sure it does. In the event that the
196 word doesn’t need to be hyphenated at all, groff leaves them
197 alone. In groff, the discretionary hyphen is entered with
198 <kbd>\%</kbd> (ie, a backslash followed by the percent sign).
201 <dt id="dropcap">Drop cap</dt>
203 A large, usually upper-case letter that introduces the first
204 paragraph of a document or section thereof. The top of the
205 drop cap usually lines up with the top of the first line of the
206 paragraph, and typically “drops” several lines lower.
207 Text adjacent to the drop cap is indented to the right of the
208 letter until the bottom of the drop cap is reached, at which
209 point text reverts to the left margin.
212 <dt id="em">Em/en</dt>
214 An em is a relative measurement equal to the width of the
216 <a href="#ps">point size</a>
218 <a href="#font">font</a>.
219 Since most Ms are designed square, an em is usually (but
220 sometimes erroneously) considered to be the same size as the
221 current point size (ie if the point size of the type is 12,
222 one em equals 12 points). An en is equal to the width of a
223 letter N (historically 2/3 of an em, although groff treats an en
224 as 1/2 of an em). Typically, ems and ens are used to measure
225 indents, or to define the length of dashes (long hyphens).
228 <dt id="family">Family</dt>
230 The collective name by which a collection of
231 <a href="#font">fonts</a>
232 are known, eg Helvetica, Times Roman, Garamond.
235 <dt id="figurespace">Figure space/Digit space</dt>
238 <a href="#fixedwidthspace">fixed width space</a>
239 that has the width of one digit. Used for aligning numerals in,
240 say, columns or numbered lists. In groff, the figure space is
241 entered with <kbd>\0</kbd> (ie a backslash followed by a zero)
244 <dt id="fixedwidthfont">Fixed width font</dt>
246 A family or font in which every character occupies exactly the
247 same amount of vertical space on the line. Courier is the
248 best-known, if not the most elegant, fixed-width font.
251 <dt id="fixedwidthspace">Fixed width space</dt>
254 <a href="#wordspace">word space</a>,
255 but does not expand or contract when text is
256 <a href="#just">justified</a>.
257 In groff, fixed width space is entered with
258 <kbd>\<space></kbd> (ie a backslash followed by a space)
262 <dt id="font">Font</dt>
265 <a href="#weight">weight</a>
267 <a href="#shape">shape</a>
269 <a href="#family">family</a>,
270 eg light, medium, bold (which are weights), and roman, italic,
271 condensed (which are shapes). By default, groff knows of four
272 fonts within its default set of families: R (medium roman), I
273 (medium italic), B (bold roman) and BI (bold italic).
274 Mom considerably extends this very basic list.
277 <dt id="force">Force justify</dt>
280 <a href="#just">justified</a>
281 text, a line needs to be broken short of the right margin.
282 Force justifying means telling a typesetting program (like
283 groff) that you want the line broken early AND that you want the
284 line’s word spacing stretched to force the line flush with the
288 <dt id="gutter">Gutter</dt>
290 The vertical whitespace separating columns of type.
293 <dt id="just">Justify/justification</dt>
295 Lines of type are justified when they’re flush at both the left
296 and right margins. Justification is the act of making both
297 margins flush. Some people use the terms "left justified" and
298 "right justified" to mean type where only the left (or right)
299 margins align. I don’t. See
300 <a href="#quad">quad</a>.
303 <dt id="kern">Kerning</dt>
305 Moving pairs of letters closer together to remove excess
306 whitespace between them. In the days before phototypesetting,
307 type was set from small, rectangular blocks of wood or metal,
308 each block having exactly one letter. Because the edge of
309 each block determined the edge of each letter, certain letter
310 combinations (TA, for example) didn’t fit together well and had
311 to be mortised by hand to bring them visually closer. Modern
312 typesetting systems usually take care of kerning automatically,
313 but they’re far from perfect. Professional typesetters still
314 devote a lot of time to fitting letters and punctuation together
318 <dt id="kernunit">Kern Units</dt>
320 A relative distance, which, by default, is equal to 1/36 of the
322 <a href="#ps">point size</a>.
323 Used between individual letters for
324 <a href="#kern">kerning</a>.
325 Different typesetting systems use different values (1/54 is
326 popular), and sometimes call kern units by a different name.
327 It is possible to change the default size of the kern unit with the
328 <a href="inlines.html#kernunit">KERN_UNIT</a>
332 <dt id="leading">Lead/leading</dt>
334 The distance from the
335 <a href="#baseline">baseline</a>
336 of one line of type to the line of type immediately beneath
337 it. Pronounced "ledding." Also called line spacing. Usually
339 <a href="#picaspoints">points</a>.
342 <em>In case you’re interested...</em> In previous centuries,
343 lines of type were separated by thin strips of—you guessed
344 it—lead. Lines of type that had no lead between them were said
345 to be “set solid.” Once you began separating them with
346 strips of lead, they were said to be “leaded”, and the
347 spacing was expressed in terms of the number of
348 <a href="#picaspoints">points</a>
349 of lead. For this reason, “leading” and “line
350 spacing” aren’t, historically speaking, synonymous.
351 If type was set 10 on 12, for example, the leading was 2
352 points, not 12. Nowadays, however, the two terms are used
353 interchangeably to mean the distance from baseline to baseline.
358 <dt id="leader">Leaders</dt>
360 Single characters used to fill lines, usually to their end. So
361 called because they “lead” the eye from one element
362 of the page to another. For example, in the following (brief)
363 Table of Contents, the periods (dots) are leaders.
365 <span class="pre" style="margin-bottom: -2em;">
366 Foreword............... 2
367 Chapter 1.............. 5
368 Chapter 2.............. 38
369 Chapter 3.............. 60
373 <dt id="ligatures">Ligature</dt>
375 Ligatures are letters joined together to form a single
376 character. The commonest are fi, fl, ff, ffi and ffl. Others
377 are ae and oe. Occasionally, one sees an st ligature, but this
378 is archaic and quite rare.
381 <dt id="picaspoints">Picas/Points</dt>
383 There are twelve points in a pica, and six picas in an inch
384 (hence 72 points to the inch). In the same way that gem-dealers
385 have always used their own system of measurement for weight
386 (carats), typographers have always used their own system of
387 measurement for type.
390 <dt id="ps">Point Size</dt>
392 The nominal size of type, measured in
393 <a href="#picaspoints">points</a>
394 from the bottom of the longest
395 <a href="#descender">descender</a>
396 to the top of the highest
397 <a href="#ascender">ascender</a>.
398 In reality, type is always fractionally smaller than its point
402 <dt id="quad">Quad</dt>
404 When only one margin of type is flush, lines of type are quadded
405 in the direction of the flush margin. Therefore, quad left
406 means the left margin is flush, the right isn’t. Quad right
407 means the right margin is flush, the left isn’t. Quad centre
408 means neither the left nor the right margin is flush; rather,
409 lines of type are quadded on both sides so that type appears
413 <dt id="rag">Rag</dt>
415 Describes a margin that isn’t flush. Rag right means the right
416 margin isn’t flush. Rag left means the left margin isn’t flush.
417 The expression "flush left/rag right" is sometimes used to
418 describe type that is
419 <a href="#quad">quadded</a>
423 <dt id="shape">Shape</dt>
425 The degree of slant and/or the width of characters.
426 (Technically speaking, this is not a proper typesetting term;
427 however, it may help clarify some concepts presented in these
431 Some typical shapes are:
434 <ul style="margin-top: -.5em; margin-bottom: -.5em">
435 <li>Roman, which has no slant, and has letterforms of
437 <li>Italic, which is slanted, and has letterforms
438 of average width</li>
439 <li>Condensed, which has no slant, but has
440 letterforms narrower than the average represented by Roman</li>
441 <li>Condensed Italic, which is slanted, with letterforms narrower
447 <a href="#font">font</a>,
448 as it is used in these documents, refers to a combination of
449 <a href="#weight">weight</a>
455 <dt id="solid">Solid/set solid</dt>
458 <a href="#leading">lead</a>
459 is added between lines of type (ie the
460 <a href="#ps">point size</a>
461 and linespacing are the same), the lines are said to be “set
465 <dt id="trackkerning">Track kerning/Line kerning</dt>
467 Sometimes, it’s advantageous to increase or decrease the amount
468 of space between every letter in a line by an equal (usually
469 small) amount, in order to fit more (or fewer) characters on the
470 line. The correct term is letter spacing, but track kerning and
471 line kerning (and sometimes, just "kerning") have come to mean
475 <dt id="unbreakablespace">Unbreakable space</dt>
478 <a href="#wordspace">word space</a>,
479 however words separated by an unbreakable space will always be
480 kept together on the same line. Expands and contracts like word
481 space. Useful for proper names, which one should, whenever
482 possible, avoid splitting onto two lines. In groff, unbreakable
483 space is entered with <kbd>\~</kbd> (ie a backslash followed by a
487 <dt id="weight">Weight</dt>
489 The thickness of the strokes of letterforms. Medium and Book
490 have average thicknesses and are the weights used for most
491 of the text in books, magazines, newspapers, etc. Light has
492 strokes slightly thinner than Medium or Book, but is still
493 acceptable for most text. Semibold, Bold, Heavy and Black all
494 have strokes of increasing thickness, making them suitable for
495 headings and the like.
498 <dt id="wordspace">Word space</dt>
500 The amount of whitespace between words. When text is
501 <a href="#just">justified</a>,
502 word space expands or contracts to make the margins flush.
505 <dt id="xheight">x-height</dt>
507 The height of a lower case letter x in a given font at a given
508 point size. Generally used to mean the average height of the
509 bowl of lower case letters.
513 <h3 id="groff-terms" class="docs">Groff terms</h3>
516 <dt id="alias">Alias</dt>
519 <a href="#macros">macro</a>
520 invoked by a name different from its “official”
521 name. For example, the official name of the macro to change
522 <a href="#family">family</a>
523 is <kbd>FAMILY</kbd>. Its alias is <kbd>FAM</kbd>.
524 Aliases may be created for any macro (via the
525 <a href="goodies.html#alias"><kbd>ALIAS</kbd></a>
526 macro) provided the alias uses a name not already taken by the
527 mom macros or one of the groff
528 <a href="#primitives">primitives</a>.
529 For a complete list of words or names you must not use, see the
530 <a href="reserved.html#reserved">list of reserved words</a>.
533 <dt id="arguments">Arguments</dt>
535 Parameters or information needed by a
536 <a href="#macros">macro</a>
537 to do its job. For example, in the macro
539 <span class="pre" style="margin-bottom: -2em;">
543 <kbd>12</kbd> is the argument. In the macro
545 <span class="pre" style="margin-bottom: -2em;">
549 <kbd>LEFT</kbd> is the argument. Arguments are separated from
550 macros by spaces. Some macros require several arguments; each
551 is separated by a space.
554 <dt id="commentlines">Comment Lines</dt>
556 <a href="#inputline">Input lines</a>
557 introduced with the comment character <kbd>\#</kbd> (ie a
558 backslash followed by the pound sign). When processing output,
559 groff silently ignores everything on a line that begins with the
563 <dt id="controllines">Control Lines</dt>
565 Instructions to groff that appear on a line by themselves, which
566 means that “control lines” are either
567 <a href="#macros">macros</a>
569 <a href="#primitives">primitives</a>.
570 Control lines begin with a period or, occasionally, an apostrophe.
573 <dt id="filled">Filled lines/fill mode</dt>
576 <a href="#just">justification</a>
578 <a href="#quad">quadding</a>.
579 In fill mode, the ends of lines as they appear in your text
580 editor are ignored. Instead, words from adjoining
581 <a href="#inputline">input lines</a>
582 are added one at a time to the output line until no more words
583 fit. Then, depending whether text is to be
584 <a href="#just">justified</a>
586 <a href="#quad">quadded</a>
587 (left, right, or centre), and depending on whether automatic
588 hyphenation is turned on, groff attempts to hyphenate the last
589 word, or, barring that, spreads and breaks the line (when
590 justification is turned on) or breaks and quads the line (when
591 quadding is turned on).
594 Nofill mode (non-filled text) means that groff respects the ends
595 of lines exactly as they appear in your text editor.
600 <dt id="inlines">Inline escapes</dt>
602 Instructions issued to groff that appear as part of an
603 <a href="#inputline">input line</a>
605 <a href="#macros">macros</a>,
606 which must appear on a line by themselves). Inline escapes are
607 always introduced by the backslash character. For example,
609 <span class="pre" style="margin-bottom: -2em;">
610 A line of text with the word T\*[BU 2]oronto in it
613 contains the inline escape <kbd>\*[BU 2]</kbd> (which means
614 “move the letter ‘o’ 2
615 <a href="#kernunit">kern units</a>
616 closer to the letter ‘T’”).
618 <p style="margin-bottom: -2em;">
619 Mom’s inline escapes always take the form
620 <kbd>\*[<ESCAPE>]</kbd>, where <kbd>ESCAPE</kbd> is
621 composed of capital letters, sometimes followed immediately by a
622 digit, sometimes followed by a space and a
623 <a href="#numericargument">numeric argument</a>.
624 Groff’s escapes begin with the backslash
625 character but typically have no star and are in lower case. For
626 example, the mom escapes to move forward 6
627 points on a line are either
629 <span class="pre" style="margin-bottom: -2em;">
630 \*[FP6] or \*[FWD 6p]
633 while the groff escape for the same thing is
635 <span class="pre" style="margin-bottom: -2em;">
642 <dt id="inputline" style="margin-top: -1em;">Input line</dt>
644 A line of text as it appears in your text editor.
647 <dt id="macros">Macros</dt>
649 Instructions embedded in a document that determine how groff
650 processes the text for output. mom’s macros
651 always begin with a period, on a line by themselves, and must
652 be typed in capital letters. Typically, macros contain complex
653 commands issued to groff—behind the scenes—via
655 <a href="#primitives">primitives</a>.
658 <dt id="units">Machine units</dt>
660 A machine unit is 1/1000 of a
661 <a href="#picaspoints">point</a>
662 when the groff device is ps. (“ps” means
663 “PostScript”—the default device for
664 which groff prepares output, and the device for which
665 mom was specifically designed.)
668 <dt id="numericargument">Numeric argument</dt>
671 <a href="#arguments">argument</a>
672 that has the form of a digit. Numeric arguments can be built
673 out of arithmetic expressions using +, -, *, and / for plus,
674 minus, times, and divided-by respectively. If a numeric
676 <a href="#unitofmeasure">unit of measure</a>,
677 a unit of measure must be appended to <em>every</em> digit in
678 the argument. For example:
680 <span class="pre" style="margin-bottom: -2em;">
684 <div class="box-important" style="margin-right: 2.5em;">
686 <span class="important">IMPORTANT:</span> groff does not
687 respect the order of operations, but rather evaluates
688 arithmetic expressions from left to right. Parentheses must
689 be used to circumvent this peculiarity. Not to worry, though.
690 The likelihood of more than just the occasional plus or minus
691 sign when using mom’s macros is slim.
696 <dt id="outputline">Output line</dt>
698 A line of text as it appears in output copy.
701 <dt id="primitives">Primitives</dt>
703 The lowercase instructions, introduced with a period, that groff
704 uses as its native command language, and out of which macros
705 are built. The majority of groff’s primitive requests are two
709 <dt id="stringargument">String Argument</dt>
712 <a href="#arguments">argument</a>
713 that is not numeric. In this documentation, string argument
714 means an argument that requires the user to input text. For
716 <a href="#macros">macro</a>
718 <span class="pre" style="margin-bottom: -2em;">
719 .TITLE "My Pulitzer Novel"
722 <kbd>"My Pulitzer Novel"</kbd> is a string argument.
725 Because string arguments must be enclosed by double-quotes, you
726 can’t use double-quotes as part of the string argument. If you
727 need double-quotes to be part of a string argument, use the
728 <a href="#inlines">inline escapes</a>
729 <kbd>\(lq</kbd> and <kbd>\(rq</kbd> (leftquote and
730 rightquote respectively) in place of the double-quote character
736 <dt id="unitofmeasure">Unit of measure</dt>
738 The single letter after a
739 <a href="#numericargument">numeric argument</a>
740 that tells mom what measurement scale the
741 argument should use. Common valid units are:
743 <span class="pre" style="margin-bottom: -2em;">
751 v (the current leading [line space])
754 <p style="margin-top: -1em;">
755 Units of measure must come immediately after the numeric
756 argument (ie with no space between the argument and the unit
757 of measure), like this:
759 <span class="pre" style="margin-bottom: -2em;">
765 The above example advances 2 line spaces and sets the line
766 length to 39 picas with a left indent of 1 inch.
769 <div class="box-important" style="margin-right: 2.5em;">
771 <span class="important">IMPORTANT:</span>
772 Most mom macros that set the size or measure of something must
773 be given a unit of measure since most of the macros do not have
774 default units of measure. There are a couple of exceptions,
775 the most notable of which are <kbd>PT_SIZE</kbd> and
776 <kbd class="bold">LS</kbd>. Both use
777 <a href="#picaspoints">points</a>
778 as the default unit of measure, which means you don’t have to
779 append “p” to their argument.
784 You can enter decimal values for any unit of measure. Different
785 units may be combined by adding them together (eg 1.5i+2m,
786 which gives a measure of 1-1/2 inches plus 2 ems).
789 <div class="box-tip" style="margin-right: 2.5em;">
791 <span class="note">Note:</span>
792 a pica is composed of 12 points, therefore 12.5 picas is 12
793 picas and 6 points, not 12 picas and 5 points. If you want 12
794 picas and 5 points, you have to enter the measure as 12P+5p.
800 <dt id="zerowidthcharacter">Zero-width character</dt>
803 <a href="#inlines">inline escape</a>
804 that allows you to print a literal period, apostrophe and, if
805 <a href="#outputline">output lines</a>
807 <a href="#filled">filled</a>,
808 a space that falls at the beginning of an
809 <a href="#inputline">input line</a>.
812 <span class="pre" style="margin-bottom: -2em;">
813 \& (ie a backslash followed by an ampersand)
816 Normally, groff interprets a period (or an apostrophe) at the
817 beginning of an input line as meaning that what follows is a
818 <a href="#controllines">control line</a>.
819 In fill modes, groff treats a space at the beginning of an input
820 line as meaning “start a new line and put a space at the
821 beginning of it.” If you want groff to interpret periods
822 and apostrophes at the beginning of input lines literally (ie
823 print them), or spaces at the beginning of input lines as just
824 garden variety word spaces, you must start the line with the
825 zero-width character.
829 <h3 id="mom-terms" class="docs">Mom terms</h3>
831 <dt id="blockquote">Blockquote</dt>
833 Cited material other than
834 <a href="#quote">quotes</a>.
835 Typically set at a smaller point size than paragraph text,
836 indented from the left and right margins. Blockquotes are
837 <a href="#filled">filled</a>.
840 <dt id="controlmacro">Control macro</dt>
843 <a href="docprocessing.html#docprocessing">document processing</a>
844 to control/alter the appearance of document elements (eg
845 headings, quotes, footnotes,
846 <a href="#header">headers</a>,
850 <dt id="docheader">Document header/docheader</dt>
852 Document information (title, subtitle, author, etc) output at
856 <dt id="epigraph">Epigraph</dt>
858 A short, usually cited passage that appears at the beginning of
859 a chapter, story, or other document.
862 <dt id="footer">Footer/page footer</dt>
864 Document information (frequently author and title) output in
865 the bottom margin of pages after page one. Not to be
866 confused with footnotes, which are considered part of
867 <a href="#running">running text</a>.
870 <dt id="head">Heading</dt>
872 The title used to identify a section of a document. Headings
873 are hierarchic, corresponding to the notion of head, subhead,
877 <dt id="header">Header/page header</dt>
879 Document information (frequently author and title) output in the
880 top margin of pages after page one.
882 <div class="box-tip" style="margin-right: 2.5em;">
884 <span class="note">Note:</span> In terms of content and style,
886 <a href="#footer">footers</a>
887 are the same; they differ only in their placement on the page.
888 In most places in this documentation, references to the content
889 or style of headers applies equally to footers.
895 <dt id="linebreak">Linebreak/author linebreak</dt>
897 A gap in the vertical flow of
898 <a href="#running">running text</a>,
899 frequently set off by typographic symbols such as asterisks or
900 daggers. Used to indicate a shift in the content of a document
901 (eg a scene change in a short story). Also commonly called a
902 scene break or a section break.
905 <dt id="parahead">Paragraph head</dt>
907 A heading joined to the body of a paragraph.
910 <dt id="pdflink">PDF link</dt>
912 A portion of text that, when clicked on in a PDF viewer,
913 navigates to a bookmarked location in a document, generally but not
914 exclusively a heading. PDF links are usually coloured to make
915 them stand out from the surrounding text.
918 <dt id="pdfoutline">PDF outline</dt>
920 The hierarchically-arranged navigation outline provided by most PDF
921 viewers (eg Okular, Evince), typically in a panel to the left of
922 the document window, and usually labeled “Contents”.
925 <dt id="quote">Quote</dt>
927 A quote, to mom, is a line-for-line setting
928 of quoted material (eg poetry, song lyrics, or a snippet of
929 programming code). You don’t have to use
930 <a href="typesetting.html#br"><kbd>BR</kbd></a>
934 <dt id="running">Running text</dt>
936 In a document formatted with mom, running
937 text means text that forms the body of the document, including
938 elements such as headings.
939 <a href="#docheader">Docheaders</a>,
940 <a href="#header">headers</a>,
941 <a href="#footer">footers</a>
942 and page numbers are not part of running text.
945 <dt id="toggle">Toggle</dt>
947 A macro or tag that, when invoked without an argument, begins
948 something or turns a feature on, and, when invoked with ANY
949 argument, ends something or turns a feature off. See
950 <a href="intro.html#toggle-example">Example 3</a>
952 <a href="intro.html#macro-args">How to read macro arguments</a>.
956 <div class="rule-long"><hr/></div>
958 <!-- Navigation links -->
959 <table style="width: 100%;">
961 <td style="width: 33%;"><a href="toc.html">Back to Table of Contents</a></td>
962 <td style="width: 33%; text-align: center;"><a href="#top">Top</a></td>
963 <td style="width: 33%; text-align: right;"><a href="using.html#top">Next: Using mom</a></td>
969 <div class="bottom-spacer"><br/></div>
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