Why do plain-text technical articles often enclose terms within backticks and single quotes?

Question

I like to save local copies of useful text-heavy pages from the web so I can practice improving their appearance by modifying the markup to include CSS.

I've noticed that some text on the pages is often delimited by ` and '.

Is there a good reason for this? I'd like to do my modifications automatically with a script if I thought these quotes were there for a good reason. Is it, for example, a byproduct of a particular authoring tool?

I have tried to search for this, but search engines treat it like empty or incomplete strings and don't give meaningful results.

A single quote example (` ') can be found in Eric Raymond's Cathedral and the Bazaar:

The problem was this: suppose someone named `joe' on locke sent me mail. If I fetched the mail to snark and then tried to reply to it, my mailer would cheerfully try to ship it to a nonexistent `joe' on snark. Hand-editing reply addresses to tack on `@ccil.org' quickly got to be a serious pain.

Answer 1

The example of Eric Raymond’s essay is a typical example of people from pre-Unicode eras trying to “improve” the typograph of their text by using conventions that no longer hold. The quoting style `' is typical of that. It’s also used in LaTeX (which automatically converts it to correct typographical single quotes ‘’).

You can see other ASCII artifacts in Eric’s essay, too: for example, he uses “--” instead of a “correct” dash “–” (an awful lot of people do this, since the dash doesn’t exist on default Windows keyboards).

As such, it’s an anachronism from a time where support for Unicode fonts (or generally: fonts lacking these typographical features) wasn’t widespread.

Answer 2

HTML doesn't. Only ' and " characters may be used to delimit attribute values (which are the only strings that can be delimited in HTML).

People writing text (which happens to be marked up with HTML) may use “,”,‘ and ’, but that is just writing using quote marks.