this post was submitted on 21 Oct 2026
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xkcd #3314: Vulnerability

Title text:

Other numbers are largely unaffected, but anyone using '4' for their certificate key is urged to upgrade to '5'.

Transcript:

Transcript will show once it’s been added to explainxkcd.com

Source: https://xkcd.com/3314/

explainxkcd for #3314

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[–] MarcomachtKuchen@feddit.org 89 points 3 days ago (2 children)

Half Life Half-Six confirmed

[–] cypherix93@lemmy.world 23 points 3 days ago (1 children)
[–] Zorque@lemmy.world 13 points 3 days ago (1 children)

Portal square root of nine

[–] cypherix93@lemmy.world 2 points 3 days ago (2 children)

I hope you mean Portal abs(square root of nine)

[–] Zorque@lemmy.world 3 points 2 days ago

You dont want to play the prequel as well?

[–] ouRKaoS@lemmy.today 4 points 2 days ago

Left 4 Dead ≈π

[–] Coffeephilic@lemmy.cafe 2 points 2 days ago

We got GTA half VI before GTA VI

[–] palordrolap@fedia.io 54 points 3 days ago (2 children)

"Half six" is fraught with peril. One slight misunderstanding and you'll have Germans and Dutch at your door when you least expect it and a bunch more people an hour later.

[–] cooltrainer_frank@lemmy.world 37 points 3 days ago (1 children)

And the Danes will think you're talking about 50

[–] ekky@sopuli.xyz 17 points 3 days ago* (last edited 3 days ago) (6 children)

*Puts on glasses* Akchually, that's only if you're counting 10's, since we count 1's as decimal and 10's in pairs of snes/snaes (20), hence fifty is half three snes or 3*20-0.5*20 = (3-0.5)*20 = 50.

Or if you're talking 1's, aka. decimal, you'd just remove the snes part, since common math is in decimal anyway, so half 3 decimal would be 3*1-0.5*1 = 3-0.5 = 2.5.

EDIT: Fun fact: 100, aka. "en hundrede/one hundred", can therefore also be called "fems" or "fem snes/five snaes". And then there's the ones who actually say "in twenty" instead of "snes", so it'd be "fem i tyvende".

[–] saltesc@lemmy.world 16 points 3 days ago (1 children)

But you never said which game on the SNES these cheat codes actually for.

[–] ekky@sopuli.xyz 6 points 3 days ago

Oh no, no game, that's how you enable the dev tools in retro-future mode. :p

[–] BigDanishGuy@sh.itjust.works 2 points 2 days ago (1 children)

That's only partly correct.

Write out the name for 50 and it becomes "halv tre sinds tyve", where "sinds" is a old word for multiply. Thus making a complete translation "half three times twenty" https://sproget.dk/sprogviden/spoergsmaal-og-svar/dansk-sprognaevn/sv00000047/

[–] ekky@sopuli.xyz 1 points 2 days ago

Huh? TIL. Well, partly. Didn't actively know about the "sinds".

So, does this mean that "snes" is just a load of bull, or are we talking different ages of counting systems? After all, just like the link explains "fyrre", the Danish counting system seems as an amalgamation of multiple counting systems and words of the time.

[–] sangriaferret@sh.itjust.works 4 points 2 days ago (1 children)

What is the origin of this system? It's nuts.

[–] ekky@sopuli.xyz 2 points 2 days ago

It's just pre-imperial. We've left everything else behind for metric, but the snaes still roams the shadows of our counting system.

Everyone knew what a snaes was and everyone measured in snaes enyway, it also happened to be about the amount that we stored fish and eggs as. So, instead of having to count all the fish, we simply asked for one snaes/box of fish. And if you needed 2,5 snaes of fish? well, then you simply asked for half three snaes.

For a very interesting example of modern culture using such improvised counting systems, look no further than the USA's obsession with measuring everything in football fields, elephants, etc..

And for an example for saying "half x"? Ask anyone who has ever said "let's meet at half six".

[–] cooltrainer_frank@lemmy.world 5 points 3 days ago (1 children)

Det ved jeg godt :)

But it's fun to show that meme off. Danish numbers are wild. My bad danish gets me mistaken numbers all the time

[–] ekky@sopuli.xyz 3 points 3 days ago (2 children)

Tænkte det nok x)

It's just fun to blow some non-Danes' minds every now and again. <3

[–] Kanda@reddthat.com 2 points 2 days ago

Every time we take the ferry to get drunk our minds are blown by fem og halv treds

[–] NochMehrG@feddit.org 5 points 3 days ago

So that’s why Duolingo hides numbers from us! (And probably also why Danish people switch to English or German no matter if you start in Danish or not..)

[–] TimeRonin@lemmy.world 2 points 2 days ago (1 children)

I would really like to understand more, why do you simplify 320-0.520 as (3-0.5)*20? Is this system actually insightful into arithmetic? Is there a good tutorial about such and such?

[–] ekky@sopuli.xyz 3 points 2 days ago

Well, it is just arithmetics.

The left side of the equation is just the natural expansion of the paranthesis to signify and drive home the point that we're specifically talking half off 20.

The middle is how it's usually represented and follows best practices. Aka. Simplifying the equation without touching the variables and constants.

The right side is the result for calculating the equation.

I'm unsure of any tutorials regarding the danish counting system, though there's bound to be some. :)

Did I misunderstand the question?

[–] techt@lemmy.world 3 points 3 days ago* (last edited 3 days ago) (1 children)

puts on novelty slinky eye glasses

Fascinating.

Also, small thing:

3*1 - 0.5*1 = 3 - 0.5 = 2.5 ----------------^

[–] ekky@sopuli.xyz 2 points 3 days ago

Nice spot ^,^' Seems not even a Dane is danish enough to Dane.

[–] Ghoelian@piefed.social 11 points 3 days ago

Can confirm this caused a lot of confusion for the 6 months i lived in the uk as a dutch person lol. Eventually we just ended up saying the numbers.

[–] jballs@sh.itjust.works 33 points 3 days ago* (last edited 3 days ago) (1 children)

The explainXKCD being down for this is kinda hilarious

[–] dfyx@piefed.social 12 points 2 days ago

explainXKCD runs on MediaWiki which is PHP, so yeah...

[–] Reygle@lemmy.world 3 points 2 days ago

I've slowly learned in life that every system, every design we rely on was thought up by other humans a LONG time ago, never updated or replaced with something new, and is within inches of crashing and burning at any single second.
If you think I'm crazy (don't worry, I most certainly do) spend a calm afternoon examining the support columns of your local bridges.

[–] NocturnalMorning@lemmy.world 6 points 2 days ago (1 children)

I'm glad I learned about this. I was about to make a private key with the number 5. Now I will make it with half 6 knowing that it's more secure, and backed by science!

[–] m4xie@lemmy.ca 3 points 2 days ago

I heard encryption is based on prime numbers. You might want to try 7.

[–] lawks@aussie.zone 11 points 2 days ago
[–] CovertOperative@piefed.zip 30 points 3 days ago

Nah man, 5 is right out.

[–] BillyClark@piefed.social 15 points 3 days ago (1 children)

In England, "half six" would mean the same as "half past six" aka 6:30.

And I've been doing this for years: If I "accidentally" get into the 10 items or fewer line with 11 items, I just tell myself it's a "baker's 10." And, of course, 12 items is a "baker's baker's 10," as we have no other name for 12.

[–] Warl0k3@lemmy.world 5 points 2 days ago (2 children)

Reinventing church numerals as a rationalisation for grocery checkout hijinks - I absolutely love this.

[–] schuelermine@leminal.space 1 points 2 days ago (1 children)

Isn't this Peano numerals? Church numerals would be if a baker's four doubled two was sixty-four.

(That being (λf. λx. f (f (f (f (f x))))) (λn. λf. λx. n f (n f x)) (λf. λx. f (f x)))

[–] Warl0k3@lemmy.world 1 points 2 days ago (1 children)

Would they not be equivalent systems for this purpose? Both use the successor function as a unary representation of the natural numbers.

[–] schuelermine@leminal.space 1 points 1 day ago (1 children)

Yes, Church numerals are something more specific. Church numerals are a model of Peano arithmetic, I think. So basically all Chuch is Peano but not all Peano is Church.

[–] Warl0k3@lemmy.world 1 points 1 day ago* (last edited 1 day ago)

Ohhh, I see what's happened!

Okay so, in this case you could make an argument that these aren't Peano numbers because this isn't an operation involving the set of all natural numbers (as in this hypothetical we're starting from 10, not 0) nor are they church numerals (as a term for a unary representation) for the same reason (and also they aren't for the other use of church numeral as the count of repeated composition [edit: and I will yoink that sidetrack ramble. bad warl0k3]), but I'm not going to do that because fuck me would that be a sign of near-terminal grass deficiency. Anyway, the above method of rationalizing grocery crimes is an example of what in computer science is generally called a church numeral, but only when working within a context that assumes base-10 representations of values are a shorthand for a unary representation of values. Whereas what generally gets called 'Peano numbers' are a purely unary expression of the natural numbers, but does not need the additional context to specify their use in this manner. I was assuming that compsci context, which I realize now that I shouldn't have been doing

Thank you, this was interesting and something I really should have been more aware of!

[–] BillyClark@piefed.social 2 points 2 days ago

I guess if I say that 1 is baker's 0, and 2 is baker's baker's 0, then I've invented the baker's unary base.

I prefer Quarter Dozen

[–] 18107@aussie.zone 8 points 3 days ago (1 children)
[–] NotAnonymousAtAll@feddit.org 5 points 2 days ago

True, but on the other hand consider https://xkcd.com/221/

[–] Xanvial@lemmy.world 4 points 2 days ago
[–] Dadifer@lemmy.world 7 points 3 days ago

XKCD spitting fire

[–] ekky@sopuli.xyz 6 points 3 days ago

Heh, reminds me of my national counting system where "halv seks" would mean 5,5. Aka. half before six, and not half of six. :P