A hard disk drive (HDD), hard disk, hard drive or fixed disk is a data storage device used for storing and retrieving digital information using one or more rigid rapidly rotating disks (platters) coated with magnetic material. The platters are paired with magnetic heads arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is accessed in a random-access manner, meaning that individual blocks of data can be stored or retrieved in any order and not only sequentially. HDDs are a type of non-volatile memory, retaining stored data even when powered off.

Introduced by IBM in 1956, HDDs became the dominant secondary storage device for general-purpose computers by the early 1960s. Continuously improved

Once upon a time it was hard to own a computer. Having a computer was such a luxury no one could easily afford. But, nowadays the number of computer owners are increased dramatically than it was guessed by the inventors. and why not ? it is the most important machine today. In the present situation of Tech world, there is no wonder if anyone says that computer is an essential part of a human.

Though you may be using the computer for many days, most probably there would be many things which were unknown to you. If you are using the computer for many days, then here is a question for you.

Have you ever wondered why the names of drives start from “C”?.

Screenshot (175)


Where had the A and B drives gone?


Here is the answer to the question:

Hard disk drives became standard since 1980. Before hard disk drives, Floppy disk drives were used as the storage devices. Floppy disk drives were the initial storage devices. They came to existence since 1960’s. Floppy disks came in two sizes 5 1/4 ” and 3 1/2″. Those two floppy disk drives were labelled as Local Disk (A) and Local Disk (B). After the invention of Hard disk, floppy disk of size 8 inch came into existence. Presently Floppy disk drives and Floppy disk drivess replaced the floppy disks.

This is the reason behind the labelling of hard drives. As a result, drives other than default drive (C) labelled as D, E etc. DVD drive and USB drive are labelled as F, G and so on.

Though “C” drive comes as the default, you can change it to A or B if you have the administrative rights.

On IBM compatible computers (PCs) running a Microsoft operating system such as Windows or MS-DOS, the hard drive is the C: drive because it is the first available drive letter for hard drives. The computer assigns the A: and B: drives to floppy disks and sometimes other removable media such as tape drives. As you install other hard drives, create new partitions, and add other drives such as CD-ROM or DVD drives, they will be assigned to other drive letters after C, such as D, E, F, G, etc.

Here is the best answer given by a quora user

During 80s and 90s the representation of A: B: were reserved for floppy drives.

A: was used for 8″ Floppy Disk Drive
B: was used for 5.25″ Floppy Disk
F: is still currently reserved for 3.5″ Floppy Drives in most windows versions

With the time, these drives went out of distribution due to better and more robust storage methods came into market.

If you still want to use these letters for fancy, Try following:

  1. Go to Start – Run
  2. Type CMD
  3. Type “subst A: C:/Windows”
    (Now check your ‘My Computer’. It has a drive named A:. Its called Virtual Drive which will take you to C:/Windows. You can use other locations as well)
    4: Create the batch file of Above command
    5: Copy the Batch file at Start – Programs – StartUp

PS: You can use any location for subst command and any drive letter(If not already in Use). Example “Subst M: D:/My Music/Linkin Park”

To Delete these Virtual Drives, Type:
“subst /M:”

Note: You can use the subst command in Linux and unix as well with “CAT on”. Be careful while deleting the virtual drive you might end up wiping your whole hard disk.


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