The Rise of the Em-Dash in Hacker News Comments

https://boazsobrado.com/blog/2026/04/15/the-rise-of-the-em-dash-in-hacker-news-comments/

by sobradob • 3 months ago

44 96 3 months ago

boazsobrado.com

ortusdux• 3 months ago

Did AI raise awareness of Em-dashes, causing more people to use them organically?

add-sub-mul-div• 3 months ago

Surely yes, but also surely neglibly compared to the rise of slop being posted. Sometimes things are what they seem!

tayo42• 3 months ago

I don't think my phone keyboard even has one to type

BoredPositron• 3 months ago

Long press on - on both iOS and android (Gboard)

JKCalhoun5• 3 months ago

Two dashes seems to collapse into an em-dash using my iPhone keyboard.

umanwizard• 3 months ago

In my case, yes. I have never used AI to write any prose (including HN comments), and I never will. But I certainly started using them more often since the ChatGPT era began, purely through osmosis. I'm not exactly proud of that, but there you have it.

razingeden• 3 months ago

I use the double dash.

This gets corrected to an emdash.

I get annoyed and put the double dash back in.

Sometimes swearing a little or grumbling “HEY. I typed what I typed” at it helps a little.

I don’t even know how many times in 20-30+ years I’ve checked some box in system or program preferences begging it to knock that off.

This is the real reason I already loathe and avoid the emdash (nitpicking over a personal stylistic preference I won’t relent on even if I’m wrong) but I can’t be the only one this happens to.

Getting piled on and called “AI” really doesn’t ease my distaste for it, but .. do people.. not write enough to understand that it brute forces its way into human copy as well?

and yes. phone posting on HN. will insert them. to my dismay.

The other one that ticks me off endlessly but I’ve finally said to hell with it and just let it go?

Turning " into “.

(Writer. Not a very good one and I’m not here to steer anyone to that drivel. But at least I’m a human one.)

Terr_• 3 months ago

I do use fewer em-dashes now, but only because I spend more time on Linux, where my habitual Windows trick of alt + 0151 no longer works.

Gormo2• 3 months ago

Press Ctrl+Shift+U to enter Unicode entry mode in GTK controls, then enter the code point for the em dash, 2014. That will produce '—'.

Although I still prefer the traditional ASCII double-dash -- easier to type, and less potential for character encoding issues. Also, LLMs don't seem to use it at all.

operatingthetan• 3 months ago

I think it's both. People started writing AI comments and also started using em-dashes. However when my former boss would write emails with AI he would add intentional typos and remove all dashes.

bitwize2• 3 months ago

I know I did. I don't want eloquent punctuation to fall exclusively to the clankers.

Sarkie• 3 months ago

My wife is a journalist and has always loved them.

Now she's been accused of using AI for her pieces.

Oh well.

bb882• 3 months ago

em-dashes help flow ideas better than other means. For whatever reason, it's easier to process in my brain a comment with an em-dash rather than trying to split the idea into separate succinct sentences.

You can do small succinct sentences, but style-wise it sucks for longer passages.

throw0101a2• 3 months ago

Now she's been accused of using AI for her pieces.

Read the observation that AI was (presumably) trained on the 'best' (or at least 'quality') writing, and so if good writers tended to use em-dashes, it should not be surprising that AI generates text with it.

But, if one's personal style included using them, you should continue to do so because why should you dial down your own voice just because someone else may be mimicking it?

ButlerianJihad• 3 months ago

For my part, editing Wikipedia raised my awareness of the different types of dashes, and when to use them appropriately. Unfortunately, my Chromebook is not so forthcoming in ease of input.

interstice2• 3 months ago

If anything I use them _less_ now thanks to this whole thing.

turtleyacht• 3 months ago

Yes. Defanging smart quotes, double-dashing em's, spelling out numbers, and swearing off emojis. Next up, double-spaced sentences.

Freedom2• 3 months ago

A reminder that according to the HN guidelines, there's no need to use underscores or other annotations to emphasize words.

jordand• 3 months ago

Unconsciously and consciously yes, and this new awareness means others are now consciously avoiding the use of them so their writing is less likely to be perceived as AI generated junk

Gormo2• 3 months ago

AI raised awareness of em-dashes among people who didn't/don't read much, especially the kind of long-form writing that LLMs have been trained on. Treating em-dashes as a tell of LLM output is a form of unintentional "vice signalling".

juped• 3 months ago

You can pry my em dash—short for "Emily's dash", after the poet—from my cold dead hands.

spudlyo• 3 months ago

Close, it's the width of the 'M' from the the famous author EMdash Forster's name. ;)

kstrauser• 3 months ago

Not even close. It's named after the em drive, after how fast it helps your thoughts flow to written word.

adampunk2• 3 months ago

WooooooOOOOOOOOooooooooOOOOOOOOOoooooo—

— A spooky ghost

WooooooOOOOOOOOooooooooOOOOOOOOOoooooo-

- A less spooky ghost

adampunk2• 3 months ago

pictured: cowards

lapcat• 3 months ago

Now someone do "the rise of Hacker News meta-analysis blog posts".

qup• 3 months ago

Serious request, I'd love to see this OP plotted against the rise of the em-dash elsewhere.

Is HN more botted, or less? And are banned accounts excluded?

meisel• 3 months ago

Gotta love starting the y-axis above 0

tmoertel5• 3 months ago

While it is generally considered a No-No to start a bar chart from a baseline that is not zero, there is no corresponding prohibition, especially among numerically sophisticated audiences, for scatter plots or line charts. In general, we want graphs to focus on the area of variation.

For example, take a look at just about any stock chart (try https://www.google.com/finance/beta/quote/GOOG:NASDAQ?hl=en). There's actual money on the line, but no baseline. Why do you think that is?

BeetleB5• 3 months ago

In general, we want graphs to focus on the area of variation.

Visually, this is vastly exaggerating the variation. Actual usage did not even double.

wtallis• 3 months ago

For stock prices, starting the y axis wherever is aesthetically pleasing makes some sense because everybody will have a different non-zero cost basis for their investment, and the graphs need to be able to clearly depict fluctuations that are minor on a percentage basis. For something like the em-dash prevalence on HN, the most meaningful question is whether it has doubled, tripled, or whatever relative to the pre-LLM corpus, and that's most clearly visually depicted by starting the y axis at precisely zero.

throwway120385• 3 months ago

The real answer actually depends. In cases where you want to visually emphasize the ratio between any pair of values, you should start from zero. In cases where only the difference between any pair of values matters and the ratio is meaningless you can start at a different baseline. A surprising number of measures are interesting in their ratio though, so we generally prefer a zero-based chart.

mcphage2• 3 months ago

take a look at just about any stock chart

Honestly, I hate that about stock charts. They adjust the axes and scales so that the graph itself provides no information. Did it go up 1 point? 200 points? 5%? 50%? You can’t tell, because the graph is just a scale free squiggle.

cosmotic• 3 months ago

And even worse, no glyph to denote the deviation

lz400• 3 months ago

I just learnt that em dash in a mac is option+shift+hyphen. I hadn't realized it was so difficult and inconvenient, and in the end it looks so similar to the other one: — -. Thin value. It's no surprise humans barely use them. Then why did it get picked up so much by AIs? I'd have imagined it's not in a lot of training data. Print media practices I guess?

hyperhello• 3 months ago

Why is that inconvenient? It’s a hyphen with modifier keys.

BeetleB5• 3 months ago

It's used a lot in LaTeX and Word. It's not as rare as people make them out to be. It's just that we haven't had a convenient way to enter it in a browser form that some of us (younger folks!) find the em-dash weird.

yojo• 3 months ago

option + hyphen gives you an en-dash (–), which is easier to type and I am guilty of way overusing/misusing.

dragonwriter2• 3 months ago

The main use of an em-dash can also be done with an en-dash set open, and different style guides have different preferences for which should be used.

dr_dshiv• 3 months ago

I love em dashes. They are so much less pretentious than colons or semicolons — and they help with flow of speech. I learned that key command a couple years ago and it made me feel so smart. I’ve had my comeuppance but I’m not stopping — just a better way to write

marssaxman2• 3 months ago

Difficult and inconvenient compared to what, I wonder? I've always really liked the Mac OS option-key system, which I found convenient and easy to understand; I sometimes wish I could type that way in linux instead of using compose keys.

mananaysiempre• 3 months ago

What is it that you like about it specifically? If you’re not picky about the choice of modifier key, you can configure the so-called “level 3 shift key” and have the em dash on the hyphen key at level four (both L3 shift and L2 aka normal shift pressed). For instance, on GNOME Wayland I have “Input Source” = “English (Western European AltGr dead keys)”, “Alternate Characters Key” (GNOME lingo for the L3 shift) = “Right Alt”, so the em dash is RAlt-Shift-hyphen.

lamasery6• 3 months ago

I grew up on Windows, Linux, and other non-Mac machines, only shifting to Macs around age 30.

Within months I was convinced that every default English keyboard I'd ever seen except the Mac one is strictly worse. It bothers me now how hard it is to get a consistent Mac-style keymap on Linux. This is one thing others should for-sure just rip off entirely. It's so much better.

UqWBcuFx6NV4r• 3 months ago

It’s neither difficult nor inconvenient, it’s just new to you.

wwalexander• 3 months ago

Apple’s text inputs usually autocorrect double hyphens to em dashes.

dragonwriter2• 3 months ago

and in the end it looks so similar to the other one:

Maybe if you are looking at it in a monospaced environment like the HN edit window; rendered in a proportional font, hyphens, en-dashes, and em-dashes are quite distinct from eachother.

It's no surprise humans barely use them. Then why did it get picked up so much by AIs?

It got picked up by AIs because their training corpus includes plenty of professionally published work, not just informal, off-the-cuff communication, and professionally published work uses typographic dashes (em-dashes, en-dashes, and even 2-em- and 3-em-dashes) extensively. (3-em less so in newer works, it having, e.g., dropped out of the recommendations of the Chicago Manual of Style as of 2024.)

Iuz2• 3 months ago

I don't comment much but I have read everything that Friedrich Nietzsche wrote, and because of him, have always used em-dashes on my writing. I think I even saw some memes in circles that discuss his work when people started realizing GPT used them a lot...

bb882• 3 months ago

I like the em-dash as well as it provides visual space more than just a "-" or a ";" or a ", and".

MikeTheGreat• 3 months ago

genuine question: How could you tell they were em-dashes?

Like, I could see some people noticing that the book they're reading has dashes that are a bit longer than normal, but what made you think "That must be it's own thing, separate from a normal dash" as opposed to something like "In this font the dashes are very long"?

Iuz2• 3 months ago

He uses it a lot, so it didn’t take long for me to notice that the dash was longer than usual. At that point, it felt less like a font quirk and more like a deliberate stylistic choice. I also recall that one of the translators mentioned his use of dashes.

nagaiaida• 3 months ago

well, hyphenation will most likely insert a lot of regular dashes for easy comparison to rule out "this font is blessed with uncommonly long dashes" and the differing uses of both en and em dashes will cluster along grammatical lines (with em dashes separating clauses and en dashes relating concepts or bounds) which ought to eventually make it clear even to someone who initially bins those together separate from hyphens.

pinusc• 3 months ago

If you know the difference between em dash, en dash, and hyphen, you start seeing it everywhere—whether thet are used correctly or not. Books tend to have correct typesetting, so if you see a dash used as an em dash ought to be used, and if it looks kinda long, you can assume it's an em dash. AFAIK often manuscripts are submitted either with hyphens or --- in place of em dashes and then the editor or typesetter fixes it.

Also, it's called em dash because it's as long as the letter m (as a rule of thumb), so it's usually an easy visual comparison. Finally, a typeface with hyphens as long as em dashes would be terrible and quite noticeably wrong!

ranger_danger2• 3 months ago

It's always funny to see people arguing that em-dash use is indicative of LLM usage, yet they don't realize where that training came from in the first place.

palmotea2• 3 months ago

It's always funny to see people arguing that em-dash use is indicative of LLM usage, yet they don't realize where that training came from in the first place.

The em-dash is indicative of AI usage when it shows up in contexts where it doesn't belong. Like informal context like forum comments and emails (though "smart" substitutions do complicate the picture a bit).

I'd only be funny if they argued it indicated AI usage in context where it does belong, like formal writing.

yencabulator• 3 months ago

That doesn't explain "The Rise of the Em Dash".

lamasery6• 3 months ago

I got my heavy m-dash use from Salinger, many years ago. When I find some distinctive habit of an author I'm reading, and it's to my taste, I often rob them.

illiac786• 3 months ago

I love em dashes. I always use it wrong, as a “pause for effect”. But it makes me smile.

BeetleB5• 3 months ago

Classic case of hacking the axis to exaggerate a point.

It went from 19.3 to 32.5. It did not even double. Which means that if you see a comment with an em-dash, it's more likely to be human than LLM.

northisup• 3 months ago

me waiting for the "the rise of posts analyzing the rise of the em-dash on hacker news" posts

jcims• 3 months ago

real unlock - https://trends.google.com/explore?q=real%20unlock&date=all&g...

key insight - https://trends.google.com/explore?q=key%2520insight&date=all...

etc.

crazygringo2• 3 months ago

How is it picking the comments?

If it's all comments, including flagged/dead/downvoted/etc., then it's not reflective of the actual filtering HN does.

But if it's weighting comments by their likelihood of being read -- e.g. mostly top comments on popular stories -- then I'd be a lot more curious.

I'm not surprised AI spam has increased substantially. But I'd be surprised if it's affected the comments most people actually read to anywhere close to the degree shown in this graph.

sobradob2• 3 months ago

Its a random-ish sample. Question, do you often use -- in your writing?

crazygringo2• 3 months ago

All the time. So funny, it's so automatic I genuinely didn't even realize I was using them in a comment about em dashes. My comment history has been full of them for over a decade by now... and I think you can tell which comments are from my phone vs my laptop by whether they're converted to — or not.

Rekindle8090• 3 months ago

I'll stand firm on my believe that no one types an em or en dash. its always an llm. its a pain in the ass to type on most keyboards, impossible on some, and pointless on phones

mcphage2• 3 months ago

It’s pretty easy on a Mac (or iPad with a keyboard)—Option+Shift+Hyphen. I do it without even thinking about how, it’s so second-nature.

xxxxxxxx• 3 months ago

This is interesting. I just fixed a Github issue where the code did not handle Em-Dash correctly. Ran some queries to check the stats there. No surprises: https://deepspaceplace.com/emdash

negura• 3 months ago

stylometric analysis can be used to profile you. so if you were using em-dashes, this is good news. it helps you blend in better than before

ChrisArchitect• 3 months ago

Related from last year:

Show HN: Hacker News em dash user leaderboard pre-ChatGPT

https://news.ycombinator.com/item?id=45071722

flowerthoughts2• 3 months ago

And here I am, just wishing that someone with the knowledge would make font ligatures that render -- and --- as en and em dashes, so I could use them more.

iamnothere• 3 months ago

Just enable the compose key, then you can hold this key (typically right alt is used) and type the number of dashes required.

https://en.wikipedia.org/wiki/Compose_key

flowerthoughts2• 3 months ago

Nice! Done. Thank you!

JKCalhoun5• 3 months ago

Some random comment turned me on to the fact that two dashes does indeed collapse to an em-dash using the iPhone keyboard.

zvr• 3 months ago

One of the minor but very welcome latest updates of Microsoft Windows was the addition of the capability to type Win+- to get an en-dash (–) and Shift+Win+- to get an em dash (—).

number6• 3 months ago

shamless self plug: https://emdashmanifesto.org/

JKCalhoun5• 3 months ago

Thank you (and I support you).

kkfx• 3 months ago

While I use it in LaTeX I tend to avoid it in non-LaTeX contexts BUT even though it's much used by LLMs having switched to EurKey layout years ago I can type it on my keyboard as well as × and many others, so it's not such a perfect AI indicator.

The Rise of the Em-Dash in Hacker News Comments

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