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610

answers:

11

Is it because the operating system is written in the C programming language? I think that the A and B languages were not so successful?

I am thirteen and trying to do computer programming in C#.

A: 

I'd say that it's because the A: and B: drives were traditionally floppy drives and early computers required you to boot using a bootable floppy disk.

I strongly doubt if the lettering has anything to do with programming languages.

Cerebrus
+6  A: 

The hard disk letter is C because historically, drives A and B were for floppy disks. It has nothing to do with the language in which the operating system is written.

David Grant
Telepathy ?? ;-)
Cerebrus
Damn -- I feel a bit old now.. this guy is young enough to never have known an era with floppies.
Nik Reiman
sqook: and don't know what so special with 8", 5 ¼" and 3½...
some
A: 

It was used on the floppy drives?

Frost
A: 

I think it's a kind of legacy from old versions of Microsoft Operating Systems where letters A and B were assigned to floppy drives.

Stefano Driussi
It would be nice to comment afted a downvote so the one receiving it could learn about his errors.Thanks
Stefano Driussi
Basically accurate information. Drive-by vote downs on SO are a nuisance but a fact of life; you learn to survive despite them.
Jonathan Leffler
+1  A: 

Its because A and B used to be floppy drives back in the days when floppy drives were the norm and there were no hard-disks. The letter C was given to any hard disk that the user installed. The drives A and B have since then been reserved for floppy drives. This has nothing to do with programming languages.

SDX2000
+7  A: 

It's a left over from the original PC designs. Originally PCs only had up to 2 floppy disk drives labelled A and B. Some time later hard disks got added and became drive C.

excalibur
Actually, there were 3 types of floppy discs.
ldigas
+1  A: 

Think DOS was working from floppy drive, and windows built on DOS continued the same drive letter convention ...

A: 

I wonder if now that computers these days rarely come with a floppy drive, it would be ok to make the primary drive be A or B. What problems might this cause?

1800 INFORMATION
User confusion. Users are used to C being their main hard disk, and A being a floppy. Even if they haven't *got* a floppy drive any more, calling the hard drive C would cause cognitive dissonance I suspect.
Jon Skeet
Meh. I'm talking about me doing it - the only user that would get confused is me. Also, my main point stands - computers these days don't even come with a floppy so why would people get confused?
1800 INFORMATION
Because there are still people alive who remember floppy drives, not to mention a wide variety of current literature that refers to the first hard disk as C:. The phrase "C drive" is still pretty common.
Rob
+19  A: 

Wikipedia gives a good explanation about the logic of drive lettering:

Except for CP/M and early versions of MS-DOS, the operating systems assigns drive letters according to the following algorithm:

  1. Assign the drive letter A: to the first floppy disk drive (drive 0), and B: to the second floppy disk drive (drive 1), if present.
  2. Assign a drive letter, beginning with C: to the first active primary partition recognised upon the first physical hard disk.
  3. Assign subsequent drive letters to the first primary partition upon each successive physical hard disk drive, if present within the system.
  4. Assign subsequent drive letters to every recognised logical partition, beginning with the first hard drive and proceeding through successive physical hard disk drives, if present within the system.
  5. Assign subsequent drive letters to any RAM Disk.
  6. Assign subsequent drive letters to any additional floppy or optical disc drives.
ISW
A: 

The origins of drive letters

*But why the letter "C"? Why not "A" or "B"? Why not "Z?"*

Unsurprisingly, the answer lies in Microsoft's old DOS roots. Long before Windows existed, most PC-compatible computer systems had only one disk drive in it - a floppy disk drive. At the time, users would insert their DOS floppy disk into the computer just before they turned it on, and the computer would start, or "boot up" via the software on the floppy. As the first and often only disk drive installed in the computer, the floppy disk was assigned the first letter of the alphabet.

Ric Tokyo
So the hard drive would be B:? :)
tehvan
No; B: was given to the second disk drive, in systems which had two floppy disk drives. Hard disks entered the scene a little later on.
Rob
yep, imagine it in incremental steps.. first no drive, then A drive.. then woohoo 2 floppy drives!! luxury
Ric Tokyo
well, first it was tape recorder, right?
Patrick McDonald
+1  A: 

Ah, floppy disks, remember those?

You could spend a whole afternoon coding your latest killer app, then find that you couldn't save it because it was too big to fit on a 5.25" single density disk.

That was when floppies really were floppy. Thin and flimsy, usually in either 5.25" or 8" sizes, though the first internal drives that appeared in PCs were 5.25". As previously mentioned, the early versions of MS Dos used to automatically assign drive A: to the first floppy drive and B: to the second. Hard drives didn't even fit into PCs back then. You could buy a 5mb Winchester Hard Disk that weighed about 30Kg and came in a big external cabinet nearly the size of a modern mini tower pc.

If your PC had twin floppies you could type a command something like "copy a: b:" to copy the contents of drive A: to drive B:

But then that was all back in a time when Bill Gates was worth about $10,000!

diskcopy a: b:, if I remember rightly
Rob
Rob: Correct. With copy you would need to define what to copy (for example, *.*)
ldigas
wow, and I thought external hard drives were relatively new, I didn't realise they preceeded internal ones :)
Patrick McDonald