[Editor’s note: This post refers and links to the 17th edition of CMOS.]

CMOS 6.117 in the Spotlight

There are two different kinds of apostrophes: smart and straight. To use them correctly, it helps to know how they work.

Smart apostrophes, also known as curly or typographer’s apostrophes, are the professional-looking marks preferred by most publishers. In word processors you will probably get them by default, thanks to a feature called smart quotes. Smart apostrophes are the marks you’ll see in this paragraph and throughout this post.

Straight apostrophes, on the other hand, are what you normally get when smart quotes aren’t enabled.

In a moment we’ll see why smart apostrophes aren’t always very smart. But first a little background info.

Apostrophes and Single Quotation Marks

The official Unicode name for the curly type of apostrophe is “right single quotation mark.” As the relevant code chart explains, “this is [also] the preferred character to use for apostrophe.”*

In other words, a curly apostrophe and a right single curly quotation mark are the same thing.

As you’ve seen throughout this post, apostrophes help to form contractions. The apostrophe’s other main role is to form possessives (as it does at the beginning of this sentence).

When this same character is being used as a right single quotation mark, it’s paired with its twin, the left single quotation mark. (Quotation marks, double or single, always come in pairs.) In Chicago and other styles that use double quotation marks, single quotation marks are rare. When they are used, they are normally reserved for quotations within quotations, “as ‘shown’ here.”†

With these curly marks (as we’ll see) it’s important to remember that an apostrophe is not the same character as a left single quotation mark. (Left and right quotation marks are also known as opening and closing quotation marks.)

Straight Quotes

The straight marks are easier to use because there’s only one kind.

QWERTY and other keyboard layouts reserve one rather than two keys for the single quotation mark and apostrophe. So there’s no separate key for the left single quotation mark. Instead, what you can normally expect to get when you press the apostrophe key is a generic straight mark. This all-purpose character has three roles: apostrophe, left single quotation mark, and right single quotation mark. ‘Here’s an example of all three.’

The straight marks are fine for correspondence and social media and the like. (They’re also the ones you’ll need if you’re typing code.) But for your published work, you’ll probably want the curly versions.

Enter smart quotes.

Smart Quotes

Smart quotes are called smart because they depend on a type of artificial intelligence known as autocorrect. At the beginning of a word, autocorrect assumes that you want a left (opening) quotation mark; in the middle of a word or at the end, you’ll get an apostrophe or a right (closing) quotation mark.

Smart quotes  are turned on by default in many word processors and other applications. (Microsoft Word introduced autocorrect, and its smart quotes feature, in 1993.)

But this system has its flaws.

The main problem is that autocorrect doesn’t do a very good job of handling an apostrophe at the beginning of a string of text, where it’s more likely to be interpreted as a left single quotation mark. So you see it everywhere, from the New York Times to social media: “The ‘90s are officially cool again.” Maybe, but that apostrophe is backward: it’s ’90s, not ‘90s. (Oops.)

Fortunately, all it takes to prevent this common error is a little bit of human intervention.

Getting the Right Mark

So how do you make sure that you get an apostrophe instead of a left single quotation mark? There are lots of ways to get the right mark when smart quotes don’t work (or when they aren’t an option). Here are a few of them:

1. If you’re using a smart quotes feature like the one in Word or Google Docs, fool your computer by typing two apostrophes and then deleting the first (incorrect) one: ‘’90s becomes ’90s.
2. Find the apostrophe in your character map or symbols menu (where it may be listed as a right single quotation mark or single closing quotation mark).
3. On a virtual keyboard, press and hold down the apostrophe key to get to the real apostrophe. This works with quotation marks too.
4. On a PC, try Alt+0146 using the numeric keypad; on a Mac, press Option-Shift-].
5. In Word (the PC version), type the number 2019 (the Unicode number for an apostrophe) and then press Alt+X. (Alt+X works both ways: put your cursor to the right of any character and then press the combination to reveal its Unicode number.)
6. In HTML, try ’ (the entity reference) or ’ (the hexadecimal character reference).

You’ll want to watch out for backward apostrophes not just at the beginning of a word but also in the middle or at the end, though those infractions are far less common. While you’re at it, make sure that single and double quotation marks are the right kind. Autocorrect has a way of mixing those up sometimes too.

For lots more on apostrophes and quotation marks, see CMOS chapter 6.

* According to the Unicode website, “The Unicode Consortium is a non-profit, 501(c)(3) organization founded to develop, extend, and promote use of the Unicode Standard and related globalization standards which specify the representation of text in modern software products and other standards.” Unicode also defines the official emoji characters. 😊

† In contemporary British style, it’s normally the other way around, ‘as “shown” here’. (The period goes after the closing mark unless it’s part of the quotation.)

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