PART I       FontSite Archives Main Page     The Rules of Typography are reprinted from the book “Digital Type Design Guide” by Sean Cavanaugh (Hayden Books).

1. Insert only a single space after all punctuation. If you grew up prior to the advent of desktop publishing, chances are you were taught to put two spaces after periods, question marks, exclamation marks, and colons. The rationale was that it is easier for the eye to distinguish sentences in this fashion. When using monospaced fonts (read: typewriter fonts), there might be some validity to this. But this only applied to documents created with a typewriter. Since the advent of the printing press in the 15th century, typesetters have never inserted two spaces after punctuation. As far as I can tell, the practice of inserting two spaces between sentences originated with high school typing teachers. It sure didn’t originate in the world of typography. I’ve heard the technique referred to as the “French method,” and despite their admiration for Jerry Lewis, I doubt even the French would adopt such a method. When preparing text for printing, regardless of the font, use only one space after all punctuation. There are no exceptions to this. Well, except one. While not necessary, it is acceptable and often more readable when composing e-mail (text that will be read online and not printed) to insert two spaces after periods, question and exclamation marks, and colons.   2. Use proper em and en dashes where appropriate. Also a throwback to the days of typewriters, two hyphens--like these--were used to make a dash because true dash characters are not available on a typewriter. But this is a major no-no in typesetting and desktop publishing, where em dashes—like these—should be used instead. An em is a unit of measure equal to the point size you are using. For example, using 10-point type, an em dash would be approximately 10 points (approx. 0.14 inches) wide, but this is dependent on the individual typeface. Actually, this is probably the widest it would be. Many typefaces have em dashes that are slightly narrower than a full em, but still considerably wider than a hyphen. Hyphens are used to hyphenate words and separate phone numbers. They should never be used as dashes. A dash, more specifically, an em dash, is a form of punctuation used to offset clauses in a sentence. An en dash is typically half the length of an em dash (sometimes slightly wider than half, depending on the typeface) but still longer than a hyphen. En dashes are primarily used to denote duration, as in 8:00–5:00, or August 12–14, or Aardvark–Adelaide. Some people use them to separate phone numbers, but I think they are too large and look awkward for this. Compare the en dash in the first example to the hyphens in the second: The hyphens appear much more natural. We are used to seeing phone numbers represented in this fashion. Some people avoid the hyphen vs. en dash question altogether by using periods or spaces to separate phone numbers: The period is preferable to the space, but this is purely a matter of personal taste. Phone numbers separated by spaces are quite common in Europe, less so in the U.S. When creating em and en dashes, you can add space before and after the dash, or not. I prefer to add either a small amount of space (usually via the application’s kerning commands), or no space at all. Page layout programs such as Adobe PageMaker and QuarkXPress let you adjust space between characters at a micro level (i.e., kerning), as do illustration programs such as Illustrator and FreeHand, but many word processors are limited in this regard and only allow you to add space via the Space Bar. The normal space created with the Space Bar seems a bit too wide for my tastes, but you may find it acceptable. Generally speaking, the wider the column of text, the more space you can insert before and after dashes (up to a full space). In a typical word processed document such as a memo or letter, for example, where your column width might be as great as 5 or 6 inches, inserting a normal space before and after a dash looks just fine. But in a document with narrower columns, say a newsletter with three columns of text, this much space will stand out, and your dashes will resemble diving boards. In this case, I would suggest adding no space at all, and simply use the program’s kerning commands (if available) to tweak the space as necessary. In PageMaker, press the Cmd key in conjunction with the Left and Right Arrow keys to decrease and increase kerning (the amount of space between characters) respectively. Hold down the Shift and Cmd keys if you want to increase or decrease kerning in smaller units. In QuarkXPress, press Cmd-Shift in conjunction with the Left and Right Bracket keys to kern text. Hold down the Cmd, Shift, and Option keys if you want to kern in smaller units. In PageMaker, a value of about 0.1 should suffice; in QuarkXPress, consider a value of about 20 before and after a dash. If you do add a full space by pressing the Space Bar, it is important to add it before and after the dash. Sometimes people will add a space after a dash to break a line. Then, if they edit the text or change the layout, the dash with a space after it but no space before will appear rather awkward looking. To create an em dash in most Mac applications, press Shift-Option-hyphen. To create an en dash, press Option-hyphen. To create an em dash in most Windows applications, press Alt-0151. To create an en dash, press Alt-0150. Some expert font sets contain a three-quarter em dash, but in reality, most em dashes are about this wide anyway. That is, most em dashes are not one em in width, and depend on the individual typeface. The three-quarter em dash can be substituted for the em dash. The two are interchangeable. But it is too wide to be used when you would normally use an en dash. It is also acceptable to use an en dash instead of an em dash to set off clauses in text. I don’t like the practice, but it’s not incorrect to do so. If you do substitute en dashes, consider adding space before and after them.