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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="#preprocessor">Pre-processor</a><br/>
114 <a href="#stringargument">String Argument</a><br/>
115 <a href="#unitofmeasure">Unit of measure</a><br/>
116 <a href="#zerowidthcharacter">Zero-width character</a><br/>
122 <div class="col-3-definitions">
123 <table class="definitions">
124 <tr><th class="definitions">Mom terms</th></tr>
127 <a href="#baseline-grid">Baseline grid</a><br/>
128 <a href="#blockquote">Blockquote</a><br/>
129 <a href="#controlmacro">Control macro</a><br/>
130 <a href="#docheader">Docheader</a><br/>
131 <a href="#epigraph">Epigraph</a><br/>
132 <a href="#float">Float</a><br/>
133 <a href="#footer">Footer</a><br/>
134 <a href="#head">Head</a><br/>
135 <a href="#header">Header</a><br/>
136 <a href="#linebreak">Linebreak</a><br/>
137 <a href="#parahead">Paragraph head</a><br/>
138 <a href="#pdflink">PDF link</a><br/>
139 <a href="#pdfoutline">PDF outline</a><br/>
140 <a href="#quote">Quote</a><br/>
141 <a href="#running">Running text</a><br/>
142 <a href="#toggle">Toggle</a><br/>
148 <h3 id="typesetting-terms" class="docs">Typesetting terms</h3>
150 <dt id="ascender">Ascender</dt>
152 The portion of a letter that extends above the bowl. For
153 example, the letters a, c, and e have no ascenders. The letters
157 <dt id="baseline">Baseline</dt>
159 The imaginary line on which the bottoms of capital letters and
160 the bowls of lower case letters rest.
163 <dt id="ballotbox">Ballot box</dt>
165 An unfilled square, usually
166 <a href="#capheight">cap-height</a>
167 in size, typically placed beside items in a checklist.
170 <dt id="bullet">Bullet</dt>
172 A small, filled circle typically found beside items or points in
176 <dt id="capheight">Cap-height</dt>
178 The height of the tallest capital letter in a given
179 <a href="#font">font</a>
181 <a href="#ps">point size</a>.
184 <dt id="descender">Descender</dt>
186 The portion of a letter that extends beneath the
187 <a href="#baseline">baseline</a>
188 (j, q, y are letters with descenders).
191 <dt id="discretionaryhyphen">Discretionary hyphen</dt>
193 A symbol inserted between two syllables of a word that indicates
194 to a typesetting program the valid hyphenation points in the
195 word. Normally, if hyphenation is turned on, groff knows where
196 to hyphenate words. However, hyphenation being what it is
197 (in English, at any rate), groff doesn’t always get it right.
198 Discretionary hyphens make sure it does. In the event that the
199 word doesn’t need to be hyphenated at all, groff leaves them
200 alone. In groff, the discretionary hyphen is entered with
201 <kbd>\%</kbd> (ie, a backslash followed by the percent sign).
204 <dt id="dropcap">Drop cap</dt>
206 A large, usually upper-case letter that introduces the first
207 paragraph of a document or section thereof. The top of the
208 drop cap usually lines up with the top of the first line of the
209 paragraph, and typically “drops” several lines lower.
210 Text adjacent to the drop cap is indented to the right of the
211 letter until the bottom of the drop cap is reached, at which
212 point text reverts to the left margin.
215 <dt id="em">Em/en</dt>
217 An em is a relative measurement equal to the width of the
219 <a href="#ps">point size</a>
221 <a href="#font">font</a>.
222 Since most Ms are designed square, an em is usually (but
223 sometimes erroneously) considered to be the same size as the
224 current point size (ie if the point size of the type is 12,
225 one em equals 12 points). An en is equal to the width of a
226 letter N (historically 2/3 of an em, although groff treats an en
227 as 1/2 of an em). Typically, ems and ens are used to measure
228 indents, or to define the length of dashes (long hyphens).
231 <dt id="family">Family</dt>
233 The collective name by which a collection of
234 <a href="#font">fonts</a>
235 are known, e.g., Helvetica, Times Roman, Garamond.
238 <dt id="figurespace">Figure space/Digit space</dt>
241 <a href="#fixedwidthspace">fixed width space</a>
242 that has the width of one digit. Used for aligning numerals in,
243 say, columns or numbered lists. In groff, the figure space is
244 entered with <kbd>\0</kbd> (ie a backslash followed by a zero)
247 <dt id="fixedwidthfont">Fixed-width font</dt>
249 A family or font in which every character occupies exactly the
250 same amount of horizontal space on the line. Courier is the
251 best-known, if not the most elegant, fixed-width font.
254 <dt id="fixedwidthspace">Fixed width space</dt>
257 <a href="#wordspace">word space</a>,
258 but does not expand or contract when text is
259 <a href="#just">justified</a>.
260 In groff, fixed width space is entered with
261 <kbd>\<space></kbd> (ie a backslash followed by a space)
265 <dt id="font">Font</dt>
268 <a href="#weight">weight</a>
270 <a href="#shape">shape</a>
272 <a href="#family">family</a>,
273 e.g., light, medium, bold (which are weights), and roman, italic,
274 condensed (which are shapes). By default, groff knows of four
275 fonts within its default set of families: R (medium roman), I
276 (medium italic), B (bold roman) and BI (bold italic).
277 Mom considerably extends this very basic list.
280 <dt id="force">Force justify</dt>
283 <a href="#just">justified</a>
284 text, a line needs to be broken short of the right margin.
285 Force justifying means telling a typesetting program (like
286 groff) that you want the line broken early AND that you want the
287 line’s word spacing stretched to force the line flush with the
291 <dt id="gutter">Gutter</dt>
293 The vertical whitespace separating columns of type.
296 <dt id="just">Justify/justification</dt>
298 Lines of type are justified when they’re flush at both the left
299 and right margins. Justification is the act of making both
300 margins flush. Some people use the terms "left justified" and
301 "right justified" to mean type where only the left (or right)
302 margins align. I don’t. See
303 <a href="#quad">quad</a>.
306 <dt id="kern">Kerning</dt>
308 Moving pairs of letters closer together to remove excess
309 whitespace between them. In the days before phototypesetting,
310 type was set from small, rectangular blocks of wood or metal,
311 each block having exactly one letter. Because the edge of
312 each block determined the edge of each letter, certain letter
313 combinations (TA, for example) didn’t fit together well and had
314 to be mortised by hand to bring them visually closer. Modern
315 typesetting systems usually take care of kerning automatically,
316 but they’re far from perfect. Professional typesetters still
317 devote a lot of time to fitting letters and punctuation together
321 <dt id="kernunit">Kern Units</dt>
323 A relative distance, which, by default, is equal to 1/36 of the
325 <a href="#ps">point size</a>.
326 Used between individual letters for
327 <a href="#kern">kerning</a>.
328 Different typesetting systems use different values (1/54 is
329 popular), and sometimes call kern units by a different name.
330 It is possible to change the default size of the kern unit with the
331 <a href="inlines.html#kernunit">KERN_UNIT</a>
335 <dt id="leading">Lead/leading</dt>
337 The distance from the
338 <a href="#baseline">baseline</a>
339 of one line of type to the line of type immediately beneath
340 it. Pronounced "ledding." Also called line spacing. Usually
342 <a href="#picaspoints">points</a>.
345 <em>In case you’re interested...</em> In previous centuries,
346 lines of type were separated by thin strips of—you guessed
347 it—lead. Lines of type that had no lead between them were said
348 to be “set solid.” Once you began separating them with
349 strips of lead, they were said to be “leaded”, and the
350 spacing was expressed in terms of the number of
351 <a href="#picaspoints">points</a>
352 of lead. For this reason, “leading” and “line
353 spacing” aren’t, historically speaking, synonymous.
354 If type was set 10 on 12, for example, the leading was 2
355 points, not 12. Nowadays, however, the two terms are used
356 interchangeably to mean the distance from baseline to baseline.
361 <dt id="leader">Leaders</dt>
363 Single characters used to fill lines, usually to their end. So
364 called because they “lead” the eye from one element
365 of the page to another. For example, in the following (brief)
366 Table of Contents, the periods (dots) are leaders.
368 <span class="pre" style="margin-bottom: -2em;">
369 Foreword............... 2
370 Chapter 1.............. 5
371 Chapter 2.............. 38
372 Chapter 3.............. 60
376 <dt id="ligatures">Ligature</dt>
378 Ligatures are letters joined together to form a single
379 character. The commonest are fi, fl, ff, ffi and ffl. Others
380 are ae and oe. Occasionally, one sees an st ligature, but this
381 is archaic and quite rare.
384 <dt id="picaspoints">Picas/Points</dt>
386 There are twelve points in a pica, and six picas in an inch
387 (hence 72 points to the inch). In the same way that gem-dealers
388 have always used their own system of measurement for weight
389 (carats), typographers have always used their own system of
390 measurement for type.
393 <dt id="ps">Point Size</dt>
395 The nominal size of type, measured in
396 <a href="#picaspoints">points</a>
397 from the bottom of the longest
398 <a href="#descender">descender</a>
399 to the top of the highest
400 <a href="#ascender">ascender</a>.
401 In reality, type is always fractionally smaller than its point
405 <dt id="quad">Quad</dt>
407 When only one margin of type is flush, lines of type are quadded
408 in the direction of the flush margin. Therefore, quad left
409 means the left margin is flush, the right isn’t. Quad right
410 means the right margin is flush, the left isn’t. Quad centre
411 means neither the left nor the right margin is flush; rather,
412 lines of type are quadded on both sides so that type appears
416 <dt id="rag">Rag</dt>
418 Describes a margin that isn’t flush. Rag right means the right
419 margin isn’t flush. Rag left means the left margin isn’t flush.
420 The expression "flush left/rag right" is sometimes used to
421 describe type that is
422 <a href="#quad">quadded</a>
426 <dt id="shape">Shape</dt>
428 The degree of slant and/or the width of characters.
429 (Technically speaking, this is not a proper typesetting term;
430 however, it may help clarify some concepts presented in these
434 Some typical shapes are:
437 <ul style="margin-top: -.5em; margin-bottom: -.5em">
438 <li>Roman, which has no slant, and has letterforms of
440 <li>Italic, which is slanted, and has letterforms
441 of average width</li>
442 <li>Condensed, which has no slant, but has
443 letterforms narrower than the average represented by Roman</li>
444 <li>Condensed Italic, which is slanted, with letterforms narrower
450 <a href="#font">font</a>,
451 as it is used in these documents, refers to a combination of
452 <a href="#weight">weight</a>
458 <dt id="solid">Solid/set solid</dt>
461 <a href="#leading">lead</a>
462 is added between lines of type (ie the
463 <a href="#ps">point size</a>
464 and linespacing are the same), the lines are said to be “set
468 <dt id="trackkerning">Track kerning/Line kerning</dt>
470 Sometimes, it’s advantageous to increase or decrease the amount
471 of space between every letter in a line by an equal (usually
472 small) amount, in order to fit more (or fewer) characters on the
473 line. The correct term is letter spacing, but track kerning and
474 line kerning (and sometimes, just "kerning") have come to mean
478 <dt id="unbreakablespace">Unbreakable space</dt>
481 <a href="#wordspace">word space</a>,
482 however words separated by an unbreakable space will always be
483 kept together on the same line. Expands and contracts like word
484 space. Useful for proper names, which one should, whenever
485 possible, avoid splitting onto two lines. In groff, unbreakable
486 space is entered with <kbd>\~</kbd> (ie a backslash followed by a
490 <dt id="weight">Weight</dt>
492 The thickness of the strokes of letterforms. Medium and Book
493 have average thicknesses and are the weights used for most
494 of the text in books, magazines, newspapers, etc. Light has
495 strokes slightly thinner than Medium or Book, but is still
496 acceptable for most text. Semibold, Bold, Heavy and Black all
497 have strokes of increasing thickness, making them suitable for
498 headings and the like.
501 <dt id="wordspace">Word space</dt>
503 The amount of whitespace between words. When text is
504 <a href="#just">justified</a>,
505 word space expands or contracts to make the margins flush.
508 <dt id="xheight">x-height</dt>
510 The height of a lower case letter x in a given font at a given
511 point size. Generally used to mean the average height of the
512 bowl of lower case letters.
516 <h3 id="groff-terms" class="docs">Groff terms</h3>
519 <dt id="alias">Alias</dt>
522 <a href="#macros">macro</a>
523 invoked by a name different from its “official”
524 name. For example, the official name of the macro to change
525 <a href="#family">family</a>
526 is <kbd>FAMILY</kbd>. Its alias is <kbd>FAM</kbd>.
527 Aliases may be created for any macro (via the
528 <a href="goodies.html#alias"><kbd>ALIAS</kbd></a>
529 macro) provided the alias uses a name not already taken by the
530 mom macros or one of the groff
531 <a href="#primitives">primitives</a>.
532 For a complete list of words or names you must not use, see the
533 <a href="reserved.html#reserved">list of reserved words</a>.
536 <dt id="arguments">Arguments</dt>
538 Parameters or information needed by a
539 <a href="#macros">macro</a>
540 to do its job. For example, in the macro
542 <span class="pre" style="margin-bottom: -2em;">
546 <kbd>12</kbd> is the argument. In the macro
548 <span class="pre" style="margin-bottom: -2em;">
552 <kbd>LEFT</kbd> is the argument. Arguments are separated from
553 macros by spaces. Some macros require several arguments; each
554 is separated by a space.
557 <dt id="commentlines">Comment Lines</dt>
559 <a href="#inputline">Input lines</a>
560 introduced with the comment character <kbd>\#</kbd> (ie a
561 backslash followed by the pound sign). When processing output,
562 groff silently ignores everything on a line that begins with the
566 <dt id="controllines">Control Lines</dt>
568 Instructions to groff that appear on a line by themselves, which
569 means that “control lines” are either
570 <a href="#macros">macros</a>
572 <a href="#primitives">primitives</a>.
573 Control lines begin with a period or, occasionally, an apostrophe.
576 <dt id="filled">Filled lines/fill mode</dt>
579 <a href="#just">justification</a>
581 <a href="#quad">quadding</a>.
582 In fill mode, the ends of lines as they appear in your text
583 editor are ignored. Instead, words from adjoining
584 <a href="#inputline">input lines</a>
585 are added one at a time to the output line until no more words
586 fit. Then, depending whether text is to be
587 <a href="#just">justified</a>
589 <a href="#quad">quadded</a>
590 (left, right, or centre), and depending on whether automatic
591 hyphenation is turned on, groff attempts to hyphenate the last
592 word, or, barring that, spreads and breaks the line (when
593 justification is turned on) or breaks and quads the line (when
594 quadding is turned on).
597 Nofill mode (non-filled text) means that groff respects the ends
598 of lines exactly as they appear in your text editor.
603 <dt id="inlines">Inline escapes</dt>
605 Instructions issued to groff that appear as part of an
606 <a href="#inputline">input line</a>
608 <a href="#macros">macros</a>,
609 which must appear on a line by themselves). Inline escapes are
610 always introduced by the backslash character. For example,
612 <span class="pre" style="margin-bottom: -2em;">
613 A line of text with the word T\*[BU 2]oronto in it
616 contains the inline escape <kbd>\*[BU 2]</kbd> (which means
617 “move the letter ‘o’ 2
618 <a href="#kernunit">kern units</a>
619 closer to the letter ‘T’”).
621 <p style="margin-bottom: -2em;">
622 Mom’s inline escapes always take the form
623 <kbd>\*[<ESCAPE>]</kbd>, where <kbd>ESCAPE</kbd> is
624 composed of capital letters, sometimes followed immediately by a
625 digit, sometimes followed by a space and a
626 <a href="#numericargument">numeric argument</a>.
627 Groff’s escapes begin with the backslash
628 character but typically have no star and are in lower case. For
629 example, the mom escapes to move forward 6
630 points on a line are either
632 <span class="pre" style="margin-bottom: -2em;">
633 \*[FP6] or \*[FWD 6p]
636 while the groff escape for the same thing is
638 <span class="pre" style="margin-bottom: -2em;">
645 <dt id="inputline" style="margin-top: -1em;">Input line</dt>
647 A line of text as it appears in your text editor.
650 <dt id="macros">Macros</dt>
652 Instructions embedded in a document that determine how groff
653 processes the text for output. mom’s macros
654 always begin with a period, on a line by themselves, and must
655 be typed in capital letters. Typically, macros contain complex
656 commands issued to groff—behind the scenes—via
658 <a href="#primitives">primitives</a>.
661 <dt id="units">Machine units</dt>
663 A machine unit is 1/1000 of a
664 <a href="#picaspoints">point</a>
665 when the groff device is ps. (“ps” means
666 “PostScript”—the default device for
667 which groff prepares output, and the device for which
668 mom was originally designed.)
671 <dt id="numericargument">Numeric argument</dt>
674 <a href="#arguments">argument</a>
675 that has the form of a digit. Numeric arguments can be built
676 out of arithmetic expressions using +, -, *, and / for plus,
677 minus, times, and divided-by respectively. If a numeric
679 <a href="#unitofmeasure">unit of measure</a>,
680 a unit of measure must be appended to <em>every</em> digit in
681 the argument. For example:
683 <span class="pre" style="margin-bottom: -2em;">
687 <div class="box-important" style="margin-right: 2.5em;">
689 <span class="important">IMPORTANT:</span> groff does not
690 respect the order of operations, but rather evaluates
691 arithmetic expressions from left to right. Parentheses must
692 be used to circumvent this peculiarity. Not to worry, though.
693 The likelihood of more than just the occasional plus or minus
694 sign when using mom’s macros is slim.
699 <dt id="outputline">Output line</dt>
701 A line of text as it appears in output copy.
704 <dt id="preprocessor">Pre-processor</dt>
706 Pre-processors are used by groff to generate tables (tbl),
707 diagrams (pic), and equations (eqn). These pre-processors are
708 fully supported by mom. In addition, the “refer”
709 pre-processor is used to generate bibliographies and lists of
710 cited works. The PDF_IMAGE macro, which allows insertion of
711 graphics into a document, is not strictly a pre-processor but
712 behaves similarly to tbl, pic, and eqn.
715 <dt id="primitives">Primitives</dt>
717 The lowercase instructions, introduced with a period, that groff
718 uses as its native command language, and out of which macros
719 are built. The majority of groff’s primitive requests are two
723 <dt id="stringargument">String Argument</dt>
726 <a href="#arguments">argument</a>
727 that is not numeric. In this documentation, string argument
728 means an argument that requires the user to input text. For
730 <a href="#macros">macro</a>
732 <span class="pre" style="margin-bottom: -2em;">
733 .TITLE "My Pulitzer Novel"
736 <kbd>"My Pulitzer Novel"</kbd> is a string argument.
739 Because string arguments must be enclosed by double-quotes, you
740 can’t use double-quotes as part of the string argument. If you
741 need double-quotes to be part of a string argument, use the
742 <a href="#inlines">inline escapes</a>
743 <kbd>\(lq</kbd> and <kbd>\(rq</kbd> (leftquote and
744 rightquote respectively) in place of the double-quote character
750 <dt id="unitofmeasure">Unit of measure</dt>
752 The single letter after a
753 <a href="#numericargument">numeric argument</a>
754 that tells mom what measurement scale the
755 argument should use. Common valid units are:
757 <span class="pre" style="margin-bottom: -2em;">
765 v (the current leading [line space])
768 <p style="margin-top: -1em;">
769 Units of measure must come immediately after the numeric
770 argument (ie with no space between the argument and the unit
771 of measure), like this:
773 <span class="pre" style="margin-bottom: -2em;">
779 The above example advances 2 line spaces and sets the line
780 length to 39 picas with a left indent of 1 inch.
783 <div class="box-important" style="margin-right: 2.5em;">
785 <span class="important">IMPORTANT:</span>
786 Most mom macros that set the size or measure of something must
787 be given a unit of measure since most of the macros do not have
788 default units of measure. There are a couple of exceptions,
789 the most notable of which are <kbd>PT_SIZE</kbd> and
790 <kbd class="bold">LS</kbd>. Both use
791 <a href="#picaspoints">points</a>
792 as the default unit of measure, which means you don’t have to
793 append “p” to their argument.
798 You can enter decimal values for any unit of measure. Different
799 units may be combined by adding them together (e.g., 1.5i+2m,
800 which gives a measure of 1-1/2 inches plus 2 ems).
803 <div class="box-tip" style="margin-right: 2.5em;">
805 <span class="note">Note:</span>
806 a pica is composed of 12 points, therefore 12.5 picas is 12
807 picas and 6 points, not 12 picas and 5 points. If you want 12
808 picas and 5 points, you have to enter the measure as 12P+5p.
814 <dt id="zerowidthcharacter">Zero-width character</dt>
817 <a href="#inlines">inline escape</a>
818 that allows you to print a literal period, apostrophe and, if
819 <a href="#outputline">output lines</a>
821 <a href="#filled">filled</a>,
822 a space that falls at the beginning of an
823 <a href="#inputline">input line</a>.
826 <span class="pre" style="margin-bottom: -2em;">
827 \& (ie a backslash followed by an ampersand)
830 Normally, groff interprets a period (or an apostrophe) at the
831 beginning of an input line as meaning that what follows is a
832 <a href="#controllines">control line</a>.
833 In fill modes, groff treats a space at the beginning of an input
834 line as meaning “start a new line and put a space at the
835 beginning of it.” If you want groff to interpret periods
836 and apostrophes at the beginning of input lines literally (ie
837 print them), or spaces at the beginning of input lines as just
838 garden variety word spaces, you must start the line with the
839 zero-width character.
843 <h3 id="mom-terms" class="docs">Mom terms</h3>
845 <dt id="baseline-grid">Baseline grid</dt>
847 Virtual guide lines spaced according to the
848 <a href="#leading">leading</a>
849 established for running text. Adherence to the grid ensures that
850 text fills the page completely to the bottom margin. Uncorrected
851 deviations from the grid result in bottom margins that fall short.
854 <dt id="controlmacro">Control macro</dt>
857 <a href="docprocessing.html#docprocessing">document processing</a>
858 to control/alter the appearance of document elements (e.g.,
859 headings, quotes, footnotes,
860 <a href="#header">headers</a>,
864 <dt id="docheader">Document header/docheader</dt>
866 Document information (title, subtitle, author, etc) output at
870 <dt id="epigraph">Epigraph</dt>
872 A short, usually cited passage that appears at the beginning of
873 a chapter, story, or other document.
876 <dt id="float">Float</dt>
878 A float is material intended to be kept together as a block.
879 Floated material that fits on a page in position is output on that
880 page. Floats that do not fit in position are deferred to the top
884 <dt id="footer">Footer/page footer</dt>
886 Document information (frequently author and title) output in
887 the bottom margin of pages after page one. Not to be
888 confused with footnotes, which are considered part of
889 <a href="#running">running text</a>.
892 <dt id="head">Heading</dt>
894 The title used to identify a section of a document. Headings
895 are hierarchic, corresponding to the notion of head, subhead,
899 <dt id="header">Header/page header</dt>
901 Document information (frequently author and title) output in the
902 top margin of pages after page one.
904 <div class="box-tip" style="margin-right: 2.5em;">
906 <span class="note">Note:</span> In terms of content and style,
908 <a href="#footer">footers</a>
909 are the same; they differ only in their placement on the page.
910 In most places in this documentation, references to the content
911 or style of headers applies equally to footers.
917 <dt id="linebreak">Linebreak/author linebreak</dt>
919 A gap in the vertical flow of
920 <a href="#running">running text</a>,
921 frequently set off by typographic symbols such as asterisks or
922 daggers. Used to indicate a shift in the content of a document
923 (e.g., a scene change in a short story). Also commonly called a
924 scene break or a section break.
927 <dt id="parahead">Paragraph head</dt>
929 A heading joined to the body of a paragraph.
932 <dt id="pdflink">PDF link</dt>
934 A portion of text that, when clicked on in a PDF viewer,
935 navigates to a bookmarked location in a document, generally but not
936 exclusively a heading. PDF links are usually coloured to make
937 them stand out from the surrounding text.
940 <dt id="pdfoutline">PDF outline</dt>
942 The hierarchically-arranged navigation outline provided by most PDF
943 viewers (e.g., Okular, Evince), typically in a panel to the left of
944 the document window, and usually labeled “Contents”.
947 <dt id="quote">Quote</dt>
949 A quote, to mom, is a line-for-line setting
950 of quoted material (e.g., poetry, song lyrics, or a snippet of
951 programming code). You don’t have to use
952 <a href="typesetting.html#br"><kbd>BR</kbd></a>
956 <dt id="running">Running text</dt>
958 In a document formatted with mom, running
959 text means text that forms the body of the document, including
960 elements such as headings.
961 <a href="#docheader">Docheaders</a>,
962 <a href="#header">headers</a>,
963 <a href="#footer">footers</a>
964 and page numbers are not part of running text.
967 <dt id="toggle">Toggle</dt>
969 A macro or tag that, when invoked without an argument, begins
970 something or turns a feature on, and, when invoked with ANY
971 argument, ends something or turns a feature off. See
972 <a href="intro.html#toggle-example">Example 3</a>
974 <a href="intro.html#macro-args">How to read macro arguments</a>.
978 <div class="rule-long"><hr/></div>
980 <!-- Navigation links -->
981 <table style="width: 100%;">
983 <td style="width: 33%;"><a href="toc.html">Back to Table of Contents</a></td>
984 <td style="width: 33%; text-align: center;"><a href="#top">Top</a></td>
985 <td style="width: 33%; text-align: right;"><a href="using.html#top">Next: Using mom</a></td>
991 <div class="bottom-spacer"><br/></div>