What's the difference between a "disc" and a "disk"? (2023) | Hacker News Reader

What's the difference between a "disc" and a "disk"? (2023)

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> In most varieties of English, disk is the preferred spelling for magnetic media (hence floppy disk, hard disk, disk drive), whereas disc is preferred for optical media (hence compact disc, digital versatile disc, optical disc).

> For all other uses, disk is preferred in American English and acceptable in Canadian English, and disc otherwise.

https://en.wiktionary.org/wiki/disk#Usage_notes

that's exactly my understanding as a non-native English speaker who haven't even read the article :-)

in my native language, they both share same word - disk (hard disk, compact disk), though floppy disk had it's own word

Also, disk is also used in "diskette", whereas disc stands alone. So as magnetic disks shrank and were called disketts on and off, they kept that spelling. Optical discs never really shrank over the years, never being called discettes.

When they shrank the disc it just became minidisc ;-) But that was technically MO, not just optical. And: it was in a cartridge so I suppose they really should have called it minidisk.

It's all photons baby, sometimes virtual.

The term "disc" for storage predates optical media. "Disc" was the common spelling for a disk (like a floppy disk) on British 8-bit computers like Amstrad CPC or Sinclair Spectrum.[1][2]

It seems like the distinction simply comes from British and American preferences.[3]

I have no idea how Apple jumped to such an arbitrary conclusion.

[1] Kempston Disc Interface manual: https://k1.spdns.de/Vintage/Sinclair/82/Peripherals/Disc%20I...

[2] Amstrad Disc Drive Interface manual: https://www.cpcwiki.eu/imgs/3/3f/DDI-1_User_Manual.pdf

[3] Etymonline entry for "disk": https://www.etymonline.com/word/disk

Disk was already the standard spelling in the UK by 1984 (in a computing context), just as program was used in preference to programme. But Amstrad mistyped it as disc on the plastic mouldings for their first CPC, and were too cheap to change them. Consequently CPC 3in disks were always called discs even into the 90s.

Did Acorn also misspell it in BBC Micro manual in 1984?

https://archive.org/details/BBCUG/page/n19/mode/2up?q=disc

That's "Akorn" and "BBC Mikro"

Big commodore Kernal vibes https://en.wikipedia.org/wiki/KERNAL#The_name

This is goofy. The difference was originally regional (US/UK), and which caught on depended on which product dominated which sub-market. There's no semantic difference.

Philips is the company that came up with the term "Compact Disc" for CDs, so we can blame them for goofing up the regional spellings and making the world more confusing.

I think Alan Shugart (or at least his team at IBM) started calling portable data disks "floppy disks," and then "hard disk" emerged to differentiate rigid disks from bendy ones. Maybe we can also blame him and his team.

The important thing is that someone gets blamed. :D

And where is the "drive" in an SSD?

Trying to explain arbitrary words with logic always fails.

Same as the Alcubierre drive! ;)

There was a subculture communicating on FIDOnet about collecting AOL installation media (3.5" disks) and reusing them. Somehow we ended up coining the term "bisk" to refer to AOL's given-away media, and much sadness was had when they moved to CDs.

So add one more to the list: a commercial disk reused for your custom .WAD files can be a bisk.

The last letter.

[Did I pass the interview? No? Understandable.]

Tron, if I remember correctly, had DISCS instead of DISKS. And if modern CPUs are RISCy, then maybe modern Intel architecture CPUs are Risky.

A disc jockey is an entertainer who spins records or compact discs to play music.

A discothèque is a nightclub where disc jockeys can perform live, spinning to create a party atmosphere for socializing and dancing.

In the United States, the word was quickly shortened to "disco" and became closely associated with the mirror ball on the ceiling and the eponymous style of music and dancing.

So when new styles of music overtook the nightclubs, they shed the "disco" appellation as well. It seems to still enjoy a lot of use in European cities, though.

A disc looks like a disc, and a disk doesn't look like a disc.

Removeable glass magnetic platters were called disk packs and definitely disc shaped (but sometimes cylindrical if it had many platters).

Always thought that “disc” was the original word for an object of a certain shape. As they evolved for computer storage, we got smaller diskettes… which were abbreviated to disks.

I certainly remember magnetic media being referred to as "disc".

For one quickly Googled example, the Sperry Univac 8433, may its heads never crash:

https://bitsavers.trailing-edge.com/pdf/univac/1100/brochure...

  sceptic - skeptic
  mollusc - mollusk
  celt - kelt
  cabob - kabob
  disc - disk

Corporate wants you to find the difference.

sceptic - someone inclined to question or doubt what they sense optically.

skeptic - someone inclined to question or doubt what they sense magnetically.

Presumably this apple page is someone's idea of an April fool, date notwithstanding.

"Disc" is the correct spelling of the flat circular thing.

"Disk" was invented by someone in the 1980s either as an attempt at a trade name, or because they couldn't spell.

Then other people continued the mis spelling.

This must be the right answer.

Apple, the etymology company.

They certainly do have bugs.

[Edit. Sorry, misread your comment as saying "entomology."]

A disk is any planar circular shape.

A disc is a disk-shaped object, such as in the form of a plastic dingus: Frisbee flying disc.

Does anyone have a spate tire? My tyre popped, probably because someone jammed a 'y' in the middle.

"Disks" as in floppy disks, are removable also. Some weird seperation choices in this 'article'.

Plus a common alternative to "hard drive" was "hard disk."

My late father never quite got out of the habit of calling it the "Winchester" - itself a nickname for a specific IBM drive model.

More modern hard disks included the drive mechanism in one unit.

They used to be separate, so you would mount the hard disk on the drive to make it accessible.

Yeah, we used to have a couple of the removable phoenix platters knocking around.

Of course now everything tends to be solid state even terms like "drive" are becoming less common.

As a quick and dirty heuristic: the C in disc is for CD (or other optical media).

Disc = round part visible

Disk = round part hidden or no round part

Have I got it!?

I think their primary difference is disc = optical, disk = magnetic. That’s what they mention first.

All of that “in the UK”.

Looking at the store, they’re using “SSD Storage” for SSD.

The British spelling was used by Philips when they launched the Compact Disc with Sony.

Disk was used by American companies inventing hard disks, floppy disks etc.

British software often used "disc" for both, e.g. RISC OS on Acorn/ARM/Raspberry Pi [1].

[1] https://arcwiki.org.uk/index.php/RISC_OS_3 (see screenshot)

Apple uses “disk” when referring to SSD storage. They still use disc when referring to a CD or DVD

Source: the language used in MacOS Tahoe

SSD could stand for "SSD Storage Device".

Bring back recursive acronyms!

SSD, of course, stands for Solid State Dis[c,k]...

Solid State Drive, usually, but when it comes to language anything goes.

A drive is a motor or other similar device, one that is driven or worked.

But there are no moving parts in an SSD.

Hence solid state.

Disck.

So a floppy disk has a disc inside?

No because they weren't optical, they were magnetic.

Yes it did. They were magnetic disks. And they were floppy. The outer case of a 3.5" was solid but just rip it open and you can see the disk itself is floppy.

Edit: oh right, you're talking about the different spellings. Those were entirely arbitrary. We mixed between the two.

Sure does.

What about bloc vs block

When I was much more active in Reddit did one time a meme for r/peloton of Froome yelling at disc brakes - but wrote it as "Old man yells at disk brakes".

Nobody told me anything so I guessed it was good grammar and such.

But then noticed everyone calls them "disc brakes"

Should be "rotor brakes"

δίσκος

Kinda surprising that the article doesn't mention the actual origin of the words:

"Disc" comes from "discus" (the plate thrown in the Olympics)

"Disk" comes from "diskette" (French for "small disc")

I probably just outed myself as a boomer assuming that was common knowledge.

Disquette*

In French we say disque for both. it's pronounced the same as disk and disc.

Both versions are disque in French. (presumably disquette for "diskette") Don't blame the French for this.

The fact of the matter is that the spelling "disk" probably entered common use from IBM who invented both the hard and the floppy disk, calling the latter the Type 1 Diskette. Enough people were exposed to the "disk" spelling from IBM usage that it kind of stuck, although in the early 1980s the spelling "floppy disc" was sometimes encountered.

You are (rightfully) saying that they semantically mean kinda the same thing. That doesn't neatly fit any branding guideline though, I'm sorry.

Pff! Disc comes from Disco!

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