UNIX man and info pages and many standard utilities use a rather unique quoting convention:

`single quotes' ``double quotes''

Other software tends to use just single or double quotes.

Where does this tradition come from?

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    Check carefully, it's not usually a single double quote at the end, it's two single quotes. '' not ". So you get ``something''. Aug 2, 2013 at 13:22
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    I think it comes from latex. But I am not sure.
    – Kartik
    Aug 2, 2013 at 13:45
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    This question appears to be off-topic because it is about typographical conventions that are not related to Unix. Aug 2, 2013 at 23:41
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    @Gilles Could have come from some technicality, though (I was thinking, maybe this once was needed to correctly parse strings). I think only the answer reveals that thas question was indeed a typographical one. By nature, it’s historical.
    – k.stm
    Aug 3, 2013 at 19:53

1 Answer 1


The oldest usage I know of is TeX. TeX uses `single-quote' and ``double-quote'' instead of 'singe-quote' and "double-quote". It uses them because opening and closing quotes are typeset differently, they curve around the quoted text. At the time, the Unicode open and close quotation marks didn't exist.

TeX was initially released in 1978 according to Wikipedia. So that's a while ago.

In many fonts, especially older terminal fonts, apostrophe (') looks like close-quote (’). And grave accent (`) looks like open-quote (‘), or at least closer to it than apostrophe does. I'm not sure if this predates TeX; it could (at least, for many plain English uses of apostrophe (e.g., Bob's machine), traditional typesetting often uses the close-quote curved character.

(Other places to look would be nroff [1973] or RUNOFF [1964]).

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