Disc and disk are varient spellings of the same word that pre-exist computing. Disc is more common in British English, Disk more common in American English. But yeah since computing came along disk has also been used more for magnetic media (hard disk) while disc has been used more for optical media (compact disc). I wouldn't be surprised if this only happened because of how the CD was marketed and branded as a "compact disc" as a trademark while hard disks and floppy disks etc were more generic terms.
In modern parlance, this has been my working understanding too:
But yeah since computing came along disk has also been used more for magnetic media (hard disk) while disc has been used more for optical media (compact disc).
Optical:
compact disc
laser disc
Magnetic:
3.5" diskette
800GB hard disk drive
...and just to point out there is some disagreement
Magneto-Optical , such as Sony MiniDisc, is sometimes referred to Disc for its optical properties and sometimes as a MO Disk for its magnetic properties.
This is correct in most cases but I don't think it's the underlying principle.
This wiki talks about the etymology, with a lot of examples. Most conform to this rule, but there are exceptions in astrophysics like an accretion disk.
Even in info tech, "hard disk" doesn't really conform to this rule. Like is a hard disk a square hard drive or is it the round thing inside? If it's the square hard drive, that's not thin enough to be a "disk". I'd it's the round thing inside that would be hard disc, but also creates problems for floppy disk because why refer to the housing in one instance but not another.
Sadly, I think the correct answer is that either refers to a thin flat thing, some spellings are preferred for some uses.
til disk is actually preferred in American English. from your link:
Usage notes
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.
A "disk" is a concept. It's an object which contains data.
"Hard" disks and "floppy" disks are always referring to the rigidity of the internal storage media. 7", 5.25", and 3.5" floppy disks have the same round magnetic storage material. The only difference with a 3.5" floppy disk is that they put a hard case over the floppy disk.
CD, DVD, Blu-ray, etc are both disks and discs, as their typically handled without a caddy/case. So technically both apply.
SSDs are still disks, just solid state, rather than floppy/hard spinning magnetic media.
Technically flash drives are also solid state disks, but we don't generally conflate the two terms for clarity.
I am not sure, but my oldest child was looking at an English brochure for a trip to France and a asked me "what the heck is a dis-coth-a-cue? Discotheque. A Disco, a dance club. And yes disco-tek is spelled Discotheque in English.
At its root this was originally a British vs. American English thing. However, the spelling of "disc" with a C has been used specifically as the trade name of various brands including both the throwable and optical media varieties, which have since become genericized trademarks.
For the optical media side of things, the name was coined by Phillips while they were consorting with Sony to develop the standard and named it the "Compact Disc" to compliment their already existing "Compact Cassette" product. They developed an official logo for the format which spelled it "disc." That's been with us ever since.
Volumes of computer storage are now colloquially referred to as "disks" because A) a significant majority of the early computer development milieu in general happened in America where we, or at least IBM, spell it with a K, and B) for a very long time, that's exactly what they were. Tape and magnetic core memory and wire loop memory were all early developments that ultimately gave way to the longstanding popularity of magnetic platter/disk fixed storage... With some exception granted to tape, which hung around for a very long time but definitely was not a random access storage medium suitable for general purpose applications whereas disks were. It's probably pure happenstance that the dominant non-fixed computer storage media also wound up being disk shaped, namely the various sizes and types of floppy disks. Computers handle linear tape based storage and random access disk based storage very differently, and nowadays random access permanent storage still has the "disk" moniker stuck to it even though it's now likely to be solid state.
As a generalized descriptor of a flat circular object, either "disk" or "disc" is appropriate but which is preferred seems to be largely depending on which continent you're from. The root of the word is indeed the Greek "discus," as in the object yeeted across the playing field by Olympic contestants.
For the optical media side of things, the name was coined by Phillips while they were consorting with Sony to develop the standard and named it the “Compact Disc” to compliment their already existing “Compact Cassette” product. They developed an official logo for the format which spelled it “disc.” That’s been with us ever since.
It did. That may have influenced the naming convention. The LaserDisc was actually originally conceived as the "DiscoVision." And if that name isn't a veritable time capsule of its era, I don't know what is.
They're all the same word at their core, evolving from the older Latin word. The difference just comes in how the words were used to describe either a computer related device, hard disk, floppy disk, or a sound carrying device, disc record, compact disc.
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.
Less commonly, disc is used for magnetic media (as in floppy disc and discette; similarly, disk is sometimes used for optical media, as in compact disk and optical disk.
The reason for this is actually pretty interesting though. Historically it was just a US/UK English difference, but it evolved into both being used because one of the first big manufacturers of optical discs, Philips, called them discs, while the US-based IBM spelled their magnetic disks with a K.
I remember when SSDs were still new, trying to install one on an older system and in the process the system needing to know the "number of sectors on the disk" which... SSDs don't have sectors. It was a confusing thing to get through at the time, but I recall figuring it out.
It's from diskette which is a portmanteau of disk and cassette which is from the early days or portable storage where cassettes were used to house disks to keep them safe from damage. For example floppy disk.
Because they form a similar job, portable storage, modern day usb pen drives and ssds are often referred to as disks.
"The spelling disk and disc are used interchangeably except where trademarks preclude one usage, e.g., the Compact Disc logo. The choice of a particular form is frequently historical, as in IBM's usage of the disk form beginning in 1956 with the "IBM 350 disk storage unit". "
This is from Hard Disk Drive (HDD), which is a Hard Drive with a Disk. Some people think the HD stands for Hard Disk, and use it incorrectly in SSD, which has no disks.
Has nothing to do with country. Discs are round objects. In the computing sense that's cds, dvds, etc.
Disks are floppy disks(diskette, "discette" never existed as a word) , hard drive disks.... etc. There is a difference and it has nothing to do with what land you're in. Disk in usa never meant a circular object like a Frisbee (discus for example)
But the floppy diskette and the "hard disks" did in fact have circular discs inside that spin around.
I suspect that the word diskette was created as an analog to tape "cassette". With both diskette and cassette, the media is stored inside an enclosure, and you don't have to take it out manually.
It's the same thing. The difference is origin. Disk is American. Disc is British. Usually the only time "disc" is used in the US, is to refer to something round. A CD could go either way, depending on the writer.
There’s been some movement over time but in general disk was used for pc because you had Hard Disk Drives. Then their counterpart the floppy diskette (disks).
Disc as a term was used for media like compact discs and subsequently digital video discs, etc. and then pc components allowing them to be read and then written to did exist for PC’s and, as such, had the disc moniker. But that’s because they were already “discs” branding wise.
USB thumb drives, being created as portable removable media for pc’s were a kind of solid state disk and so they use the k. Even NVME, being primarily storage for computing devices, can also colloquially be called “disks” but more and more people just refer to them as drives and I suspect those who refer to them as disks may do so out of older computer hardware habits and that utilities (fdisk, df, etc)call any such media a “disk”.