Ten common mistakes in the typesetting of technical documents

Charles Poynton

Copyright © 1998-02-08 rev 2013-03-26

The widespread use of word processors has permitted – even forced – many technical authors to typeset their own work. But most technical authors have no familiarity with the principles of typesetting. This note catalogs what I consider to be the ten most common mistakes, in descending frequency of incidence.


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1. Failure to provide clear title, author, and pages

A surprising number of technical authors fail to clearly identify their work. You probably want your reader to be certain who wrote the work, to cite it, and to determine whether he or she has the most recent version. So, provide a title, your name, and a version or date on the first page. Number your pages. Either place a notation such as 1 of 4 on the first page, or use a typographical device (such as ■) as the final character of the work.

Curiously, in the original paper describing the technical foundation of Google, the authors neglected to put their names on the paper! Bibliographic data, including the identities of the authors, can be found at the Stanford InfoLab Publication Server entry. The paper itself is available in PDF format:

Larry Page, Sergey Brin, Rajeev Motwani, and Terry Winograd, The PageRank Citation Ranking: Bringing Order to the Web, Stanford Digital Library Technologies Project publication 1999-6 [accessed 2013‑03‑26].

2. Lack of consideration for line length and type size

A 66‑character line is widely regarded as ideal for readability. With 12-point Courier type – so-called Pica, with ten characters per inch – 66 characters make a 6.6‑inch line. Set on an 8.5‑inch page width, this leaves a reasonable margin of about an inch on each side. But 12‑point type, especially Courier, is too large for all but very unusual cases. With 10‑point Palatino, quite suitable for a technical document, a typical 6.6‑inch line has 100 characters, far too many for continuous reading. To use 10‑point Palatino, a line length of about 4.125 inches would be ideal. If you want to use a single column, consider using 11‑point type in a column about 5 inches wide. If your document is almost wholly text, consider using 9-point type in a layout with two 3‑inch columns.

3. Thoughtless use of monospace fonts

In the Courier typeface, and other typefaces restricted by the mechanical constraints of typewriters, the letter i is forced to have the same set width as the letter W. It is quite legitimate to use Courier, or another monospace font, if you want your document to look like it was produced on a typewriter. But if you want a document to appear attractive and permanent, choose a proportional font.

4. Gigantic heads

It is obviously necessary to distinguish headings (or heads) from body text. Normally, a head is placed in the margin, or set off by spacing. In these circumstances, it is unnecessary to set the head in a size larger than the body type, and usually unnecessary to use a different font family. If you are unfamiliar with typesetting, simply set the head in boldface type of the same size as the body face.

5. Unsightly indication of emphasis

Underlining is strictly for typewriters. Modern word processors and page layout programs give access to italic typefaces: Use italics for emphasis. To use boldface would make your page look blotchy. Use quotation marks only for their intended purpose: quotations. To use quotation marks for emphasis is disruptive to smooth reading of your text.

6. Inappropriate use of typewriter conventions

Follow the period at the end of a sentence by a single space, not two. Use a single paragraph mark to terminate a paragraph, not two. On a typewriter, you are forced to set two hyphens in place of a dash, but in typeset work you can use an en dash – like this – surrounded by normal (word) spaces. To achieve spacing, or to force a paragraph to the top of a page, use your word processor's spacing and positioning controls instead of blank lines. It is wrong to set two hyphens in place of a dash: Use an en dash surrounded by normal (word) spaces. Modern word processors and page layout programs allow you to use typographic characters. To denote minutes, seconds, feet, and inches, spell the unit or use letter abbreviations for the benefit of your international audience. The proper symbols are prime (′) and double prime (″); use the straight single and double quotes ' and " only if the proper symbols are unavailable and insufficient space is available to use min, sec, ft, or in. For an apostrophe, use the proper typographical symbol (’); for quotations, use typographer’s “curly” quotes. (These may be accessible through your word processor’s smart quotes feature.)

7. Lack of control of line breaks

Modern word processors allow you to control line breaks and hyphenation. Use a nonbreaking space to prevent adjacent elements – such as a numerical quantity and its associated unit – from being separated by a line or page break. Use a nonbreaking hyphen to avoid the elements of a compound modifier, such as 35‑millimeter, from being broken at a line-end.

8. Failure to clearly distinguish paragraphs

A surprising number of technical authors fail to clearly separate their paragraphs. This makes their work hard to read. Choose one of two methods to identify paragraphs: Either indent the first line of every paragraph, or use no indentation and establish paragraph formatting such that paragraphs are separated by the equivalent of a blank line.

9. Careless setting of fractions

Set a fraction using superscript for the numerator and subscript for the denominator. Use the fraction slash character as a separator – on a Macintosh, access it as Shift‑Option‑1.

10. Poorly oriented figures

If your document includes figures oriented differently from the text, it will be necessary for the reader to rotate your document. You must ensure that he or she has to turn the document only once per page, and always in the same direction. I suggest that you arrange the layout so that the reader rotates the body text clockwise 90 degrees to view a figure. In other words, when viewing the text in its natural orientation, place the top of a rotated figure to the left. ■

Charles Poynton