Editing Backtick (section)

===As surrogate of apostrophe or (opening) single quote===

Some early ASCII peripherals designed the backtick and apostrophe to be mirror images of each other: {{char|&#x201B;}} and {{char|&#x2019;}}.<ref>{{Cite web |first=Markus |last=Kuhn |url=http://www.cl.cam.ac.uk/~mgk25/ucs/quotes.html |title=ASCII and Unicode quotation marks |quote=Please do not use the ASCII grave accent as a left quotation mark |publisher=Department of Computer Science and Technology, University of Cambridge}}</ref> This allowed them to be used as matching pairs of open and close quotes while still being somewhat usable as grave and acute accents, made apostrophes typographically correct, and allowed the apostrophe to be used as a prime. This had a number of problems that led most modern systems and Unicode to render the apostrophe as a "straight" one:
* Open quote is not typographically correct: the correct form ({{char|&#x2018;}}) is flipped vertically from what is shown here.
* No matching double quotes, although two single quotes looked acceptable on proportionally-spaced devices.
* Wrong appearance if used as overprinted diacritics.
* Lots of software and documents used the apostrophe for opening as well as for closing quotes.

This can still be seen in documents and email from that time (before 1990), and in output generated by some UNIX console programs such as [[man pages]]. Institutions that traditionally had used it have abandoned or deprecated it.<ref>{{Cite web |quote=<nowiki>In the C locale, the output of GNU programs should stick to plain ASCII for quotation characters in messages to users: preferably 0x22 (‘"’) or 0x27 (‘'’) for both opening and closing quotes. Although GNU programs traditionally used 0x60 (‘`’) for opening and 0x27 (‘'’) for closing quotes, nowadays quotes ‘`like this'’ are typically rendered asymmetrically, so quoting ‘"like this"’ or ‘'like this'’ typically looks better.</nowiki> |url=https://www.gnu.org/prep/standards/html_node/Quote-Characters.html#Quote-Characters |title=GNU Coding Standards: Quote Characters |work=GNU Coding Standards |publisher=[[Free Software Foundation]] |date=19 February 2019 |access-date=12 March 2019}}</ref><ref>{{cite web |url=https://lists.gnu.org/archive/html/bug-texinfo/2012-01/msg00026.html |title=<nowiki>makeinfo should quote 'like this' instead of `like this'</nowiki> |first=Paul |last=Eggert |date=23 January 2012  |work=bug-texinfo Archives |access-date=27 March 2018}}</ref>