Key Terms Every Editor Should Know

CMOS Glossary in the Spotlight

In editing as in life, things tend to come in pairs. Life has its ups and downs, left and right, sea and land, victory and defeat. In editing you have capitals and lowercase, justified and ragged right, insert and delete.

A lot can be learned about a concept by considering terms that mean the opposite of each other or are related in some other way. So we turned to CMOS in search of such pairs, starting with the glossary.

We came up with a lot, but what stood out most were all the terms related to letters and numbers.

The Right Type

Probably no one spends more time examining words on the page or screen than editors do. It can help to know something about those shapes you’re staring at all day long.

typeface v. font. Most people these days use the words typeface and font to mean the same thing. Strictly speaking, however, Times New Roman and Adobe Caslon are typefaces—a collection of fonts with a common design. Font, then, refers to a specific style of type at a specific size—for example, twelve-point Times New Roman regular or eighteen-point Adobe Caslon semibold italic.

Editor’s takeaway: In the apps that we use all day to do our work, a typeface is a font, so unless you’re editing a book on type design, you can knowingly disregard the difference—unless it happens to be trivia night. (In this post, we’ll stick to font when we need to refer to one or the other.)

old-style v. lining figures. Old-style figures (also called text figures) resemble letters. (Note that a figure in this context is a number expressed as a numeral.) Like letters, old-style figures feature ascenders and descenders, as in the stem on a lowercase d (an ascender) or the tail on a lowercase p (a descender). In the following example featuring Lyon Text (a font that also includes lining figures), note the descenders on 3, 4,5, 7, and 9, and the ascenders on 6 and 8:

Old-style figures

Lining figures, on the other hand, resemble letters in all caps. (Lining figures, which are also called modern figures, emerged somewhat later than old-style figures in the history of printing and typesetting.) Instead of featuring ascenders and descenders, lining figures align at their tops and along the baseline, the imaginary line that all letters and numbers rest on. Here’s an example in Times New Roman:

lining: 0123456789

Editor’s takeaway: Depending on the font, a zero in old-style figures may look more like the letter oh, and a one may look like a roman numeral one. Knowing this may help you recommend lining figures—or words rather than numerals—in a context where old-style figures may be ambiguous.

monospaced v. proportional. In a monospaced font (or fixed-width font), each letter, number, or other character (including punctuation) takes up the same amount of space. For example, in Courier New, a popular font designed to mimic a typewriter, the ten-letter synonyms Copyeditor and Amanuensis are of equal length:

Copyeditor Amanuensis

In a proportional font (Lyon Text again), they are not; note, for example, how an i takes up less space than an m:

Copyeditor Amanuensis

A related concept applies to figures. Letters and numerals in a proportional font are usually proportional, but some proportional fonts also feature a tabular set of figures in which each of the ten numerals takes up the same amount of space (as in a monospaced font). They’re called tabular because they line up in tables.

Editor’s takeaway: Normally you won’t have to worry about proportional versus monospaced, but if you notice that the figures in a table aren’t lining up properly (especially along the decimal), you may suggest that tabular (monospaced) figures should be used instead of proportional.

serif v. sans serif. A serif is a small projecting line or wedge on the main stroke of a letter. Most fonts used for the text of published books have serifs. Sans serif fonts, as the name suggests, don’t have these extra bits. Here’s what that looks like (in Lyon Text and Microsoft Calibri, respectively):

Serif, Sans serif

Editor’s takeaway: Opinions differ about when to use serif or sans serif, so the decision is best left to a design pro. But editors might run across a case where a sans serif font isn’t suitable—for example, if the meaning of the text depends on being able to see the difference between a capital letter I (as in the first-person pronoun) and a lowercase l (el). For this reason, many writers and editors avoid sans serif fonts at the manuscript stage.

kerning v. letterspacing. Letterspacing, also known as tracking, refers to the average space between letters (and other characters) in a line of type. In justified text (covered below), letterspacing may be adjusted to allow the letters to fill out the line—though not to the degree shown in the first two lines in the following example:

This line is far too loose; this line is far too tight (unless you like things squished); this line, meanwhile, is more or less perfect.

Kerning, on the other hand, refers to a specific instance of letterspacing between two adjacent characters that may overlap. Note in the following example how the serif on the V overlaps with the o in the first line (in proportional Lyon Text) but not in the second (in monospaced Courier New):

In this context, the serif on the V is also known as its kern.

Editor’s takeaway: Proofreaders, who usually work with text that’s been edited and formatted for publication, will especially want to watch for and flag lines that are too obviously loose or tight—as in justified text (see next item). Hyphenation and other adjustments may be necessary to allow for better spacing.

justified v. ragged right. Text that’s justified (in what is also referred to as full justification) aligns on both the left and the right margins. Justified text depends on automatic adjustments to the space between letters and words. Text with a ragged right margin (like the text in this post) doesn’t require any such adjustments.

Editor’s takeaway: Justified text will require attention to loose or tight lines at the proofreading stage (as discussed above). With a ragged-right (or sometimes left) margin, on the other hand, the words fall where they fall; however, if hyphenation is allowed, the occasional adjustment may be in order.

More Pairs

Did you know all of those terms? Here are a few more.

insert v. delete. In pencil-edited copy, a carat (^) shows where to add text, which is in turn written in wherever there is space to do so. Deletions are struck through with a line, sometimes with a loop at the end of it. Onscreen, changes are marked automatically—for example, with inserted text underlined, like this, and deleted text struck through, like this. (For a detailed overview of the editing process, including illustrations, see chapter 2 in CMOS.)

redline v. blackline. Redline and blackline both describe a document that’s been marked up to show changes. The former term invokes the editor’s red pencil; the latter is common in law (where it may be referred to as a legal blackline). Many editors use redline to refer to any marked-up document.

editor’s style sheet v. electronic style sheet. An editor’s style sheet is a document that specifies how certain words should be spelled, whether to use a serial comma, and other matters of editorial style. An electronic style sheet, by contrast, is a set of programmatic instructions that applies font styles, indents, and other formatting attributes to a document intended for the screen. Web pages and e-books typically depend on CSS (cascading style sheets).

HTTP v. HTTPS. The abbreviation HTTP stands for “hypertext transfer protocol”—the basis of hyperlinked pages on the internet. The version with the S, which stands for “secure,” supports encryption and other security measures. A URL beginning with http:// will usually redirect to the https:// version if it is enabled.*

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Other pairs include typesetter v. compositor (which are synonymous); vector graphic v. bitmap (vectors are smooth at all sizes, whereas bitmaps lose clarity as they are enlarged); cloth v. paper (as in hardcover and paperback books); ASCII v. Unicode (old-school character encoding v. modern); widow v. orphan (the first line of a paragraph stranded at the bottom of a page is an orphan; a widow is a short last line stranded at the top of a page); SMALL CAPS v. ALL CAPS (as illustrated here); subscript v. superscript (as in H2O or E = mc2); and arabic v. roman numerals (3 v. III).

You’ll find all these and more in our glossary. For a related but more technical discussion, see How Books and Journals Are Produced.


* As of 2017, when the seventeenth edition of CMOS was being published, many sites were in the process of upgrading their security, so you’ll see a mix of http:// and https:// in our examples.

Top image: Yin yang emoji, Microsoft rendering.

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