I almost use them interchangably. I know I probably shouldn't and I find myself asking that same question nearly every time I type one or the other, but then usually decide that the reader will know what I'm saying and not worry about it.
The main reason that disc is in my vocabulary is because of CDs. Those are Compact Discs, though most other uses of the word on computers uses the disk spelling. Hard Disk, Floppy Disk, etc. I typically called those drives rather than disks, so my use of the word in reference to CDs probably influenced my thoughts there.
I also typically use rotor rather than disk/disc when referring to the brake part, so I generally used the disc spelling a lot more than the disk spelling over the years.
ha ha ha /\ that is always my question because it seems like one is the american spelling and one is the english spelling. but i never remember so i write it both ways.
This topic got me curious so I consulted google and it looks like you are kind of right.
Doesn't seem so much a British vs American thing, but definitely different etymologies (origins) and preferences of use. Seems that Disk originated from the greek word diskos, while disc originated from latin discus. The greek diskos referred to a round flat object (a disk) that was thrown for distance. Discus in latin referring to a shape of an object (disk, dish), though has since evolved to be used for the sport where a round flat object (a disk) is thrown for distance. Seem that since antiquity, the two have been used nearly interchangably. Disc is more comon in british english while disk is more common in american english, though both use both interchangably.
According to Marriam-Webster: "
Disc is seen more often in the music industry and throwable objects such as Frisbees, whereas
disk is the preferred spelling in computer-related lingo such as
floppy disk."
Well based on that explination, I can tell you for sure that some times the correct word to use can vary for the same object. It might be hard
disk or floppy
disk when installed in a computer, but as soon as it pisses me off it's liable to be come a hard
disc or floppy
disc as it flies across the room. The article doesn't mention brakes.
I would say disc is probably the correct spelling when referring to a brake system, since the rotor can be both musical and a throwable object like a frisbee. Like the computer parts above, it it pisses me off enough I will make it fly across the room and, depending on who it hits on the way, it might also be a musical instrument. It makes music while pounding on it with the 5lb sledge to get it to come off, and it makes music when it finally pops off and lands on my foot. Yes, if the language in a lot of (c)Rap can be called music, then my cussing and swearing can too.
Now back to your regularly scheduled break discussion...
(Yes, I intentionally misspelled break since it's another common homonym found around brake discussions)
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