ASCII has a limited number of characters, so they designed it so some do double-duty. The grave could be a grace accent if you backspaced over a letter, or it could be an opening quote mark. The apostrophe was the reverse: it could be the acute accent. The fonts were drawn so these characters were angled enough to be accents, but also looked like quote marks. The apostrophe wasn't a vertical prime sign. Angle brackets and greater/lesser-than also double-up.

It's the grave accent - pretty rare in English outside of loan words from other languages.

https://en.wikipedia.org/wiki/Grave_accent#English

Touché

I am not claiming to be a learnèd man, but I believe that is an acute accent, not a grave accent.

You are absolutely correct. Je suis désolé.

I think back in the day (typewriters thru... 90s?) you wrote quoted text `like this.'

This is how both TeX and m4 do quoting by default so presumably common when they were created (mid-eighties and early seventies respectively IIRC)

It’s an ASCII approximation of the proper typography for single quotes (except when you’d use inverted quotes for some reason, not sure how common it is in English).

Similarly, LaTeX uses `` and ‘’ for double quotes because the opening and closing symbols are not the same in properly typeset texts.

This still seems to be "house style" for a certain brand of "old school" open source mailing list.

Note that ' is not technically a proper apostrophe which would be ’ instead. It only came to be thanks to typewriters having limited character space.

> What is it?

Not sure if you meant this literally, but I've seen it refered to as a back tick. As to what it's for, I have no idea either. I can't recall ever seeing it outside of programming.

On a mechanical typewriter you'd have a button that would "revert" the position you'll write to by one character - also known as backspace.

So if you pressed backspace followed by "`", you'd give the last character a grave accent.

That's my theory for it being called backtick anyways.

Nowadays you could configure your input method to make that key give the next character a grave accent

I'm pretty sure it's called "back" because of the direction it tilts.

My mum had a mechanical typewriter and yes it would do that. However English has no formal diacritics. We do have shit loads of borrow words from French and others that do have them.

If the back tick on the en_GB keyboard is a sop for the grave accent, then why do we not have an acute accent available as well? or a cedilla for that matter?