As you probably know, any time you use a Windows
PC, you're typically ALWAYS going to see the main installation drive as the C drive. And
you've probably seen that whenever you plug in additional storage devices, whether a USB
drive, an internal drive, an SD card or whatever, that it will get assigned some other letter
after C, like D E F and so on. But you might have wondered, why is the main
drive C, wouldn't it make sense to make A: the main drive? And why, if you plug in more
devices, do they NEVER get assigned as A or B? And how does Windows assign drive letters
anyway? And wait, operating systems like Mac and Linux don't have drive letters, how do
THEY work? Well hold on, let's take this one at a time, and by the end you'll know more
than you will ever need about all these questions, but it's still pretty interesting. First off, let's not keep you in suspense
and longer about the A and B drives. The reason you never see A and B drives automatically
assigned, is they are basically reserved for floppy disk drives. Yes you heard that right,
it's a hold-over from the old days. You see, back in the early 1980s, the first personal
computers actually rarely had hard drives. They were an optional, but very expensive
feature. Instead computers mostly just used floppy drives. In fact, in the first version
of DOS 1.0, it only supported floppy drives, not hard drives at all. Microsoft then bought
DOS and re-wrote much of it and rebranded it as MS-DOS, and MS-DOS 2.0 did support hard
drives. But even through MS-DOS version 4.0, when
the computer booted up, floppy drives were assigned letters before hard drives were.
So for example, if you had four floppy drives and a hard drive, the floppy drives would
get A B C and D, and it would assign the hard drive as E, as like an after thought. It wasn't
until MS-DOS 5.0 that the letter C was always assigned to the first hard drive. A and B
were still only for a primary and secondary floppy drive, but any additional device after
that would would just go down the alphabet, from D on. And I was curious if Windows 10
would actually assign a floppy drive to A to this day, so I actually ordered a USB floppy
drive, plugged it in, and sure enough, it got assigned to the letter A. Now you may notice here that I actually do
have an SSD mounted to B. That's because the A and B reservation is only for Windows automatically
assigning the drive letter. But you can actually do it yourself through the disk manager, and
you can even assign a drive to the letter A if you want. I still have C as my main drive
of course, but figured why not use B too for one of my extra drives, though I did keep
A open for whatever reason. Having an A drive just didn't feel right. And actually from what i've been reading,
it is technically possible to change the main drive letter on Windows from C to something
else. Although it does involve a little bit of work and messing with the Windows registry
I think. So it could potentially break some stuff. However, that might not be the best
idea for compatibility, because some programs may just assume C as the main drive path,
because it pretty much always is, which might cause issues with that program if it's not.
Over the years, I have seen the occasional program, it's very annoying, but it will only
let you install the program to the C drive, so I have no idea what they'd do if there
WAS no C drive. Alright, so no we know how Windows works with
drive letters, but what about Linux and Mac? Well they don't even have drive letters, the
drives just have names, but it is a bit more complicated than that. With Linux, you have what's called the Root
directory, which is the highest level path of the entire file system. You can't back
up any further, so to speak, sort of like the My Computer view in Windows, also called
"This PC" in Windows 10, where it shows you all the stuff attached. Of course the My Computer
view isn't really a path in itself, it just shows you the devices. Except in Linux, the
root is an actual path, and it's also sort of like the main C drive in Windows. If you
open the root directory, you do see a bunch of folders. These can be either actual folders
on the drive, or so-called 'mount points', which you can sort of think of as virtual
folders or shortcuts. You might be thinking, wait, if the root folder
is as far back as you can go, how does it handle more drives? Because there is no 'My
Computer' equivalent in many linux distros. Well instead of getting a drive letter, you
would instead 'mount' a drive with a path name. Let me explain. So say you install a
second hard drive, you can mount it as /secondary/, where the first slash is the root directory,
and then 'secondary' becomes the name of the mount point, which again basically is like
a virtual directory that goes into the root directory. And then if you enter into that
directory, it will show you what ever is in the hard drive. And by the way, you can call
it whatever you want though, it doesn't have to be 'secondary', I just made that up. But
now for any files that are in there, the path for them will start with '/secondary/whatever
else'. But what's also different in Linux, is many
devices are commonly mounted with a mount point in a path called 'mount' or possibly
'mnt'. So for example if you have a USB drive, it might be mounted as /mnt/USB, so to get
to it, you'd have to go to the root directory, then mnt, then USB. You COULD mount it into
the root folder, but apparently it's common practice to organize mounted things into their
own directory. Don't worry if you can't quite wrap your head
around the file system in Linux, just know that instead of using drive letters, Linux
lets you mount it as any name and path. When it comes to Mac OS it's actually similar
to Linux, because again there are no drive letters, it just shows the drive's name. Though
Mac does make it a bit easier on users by simplifying everything by hiding all the root
directory stuff. Instead, if you use the file explorer called Finder, you can view an equivalent
of My Computer from Windows, where it does actually show you the drives, network devices,
etc. So it's way more intuitive on Mac, and doesn't just show you a bunch of root folders,
at least to the user. In the back end, I do believe MacOS still has a file structure similar
to Linux, because they're both based on UNIX. Now you might be thinking, this is so confusing,
why is Linux so weird? But you might be surprised that Windows can ALSO mount drives as paths,
not just letters. For example if I plug in a USB drive, you can see it gets auto assigned
the letter L. In disk manager, I can right click it and select 'Change Drive Letter and
Paths', where I can change the drive letter where it shows L, but I can also add a mount
point by hitting Add. Now see the option that says 'Mount in the following Empty NTFS folder'.
NTFS is just the Windows filesystem, so basically it's saying you can pick any empty folder.
So I'll make a folder anywhere, like on the desktop called WhateverUSB, then navigate
to it and select that as the mount point. So now if I go into that 'folder', (it's not
really a folder it just looks like one), well this is weird, it actually goes into the USB
drive. And from here, the path is listed as being in the C drive, then Users/Joe/Desktop/whateverUSB.
And instead if I go to This PC like I normally would, I can also see the same USB drive as
the letter L, with all the same stuff inside it. So it has two mount points, or two paths
that access directly to that drive. I can even remove the letter L completely, and it
will warn you that some programs only work with drive letter paths. But if I do it anyway,
now it doesn't even show under This PC, but it is still mounted and accesible in the desktop
path. Now what's also interesting, is if I unplug
the USB drive, the mount point actually sticks around on the desktop, but it's just inaccessible.
Then if I plug it back in, I can once again access the drive from that mount point. Another notable thing about this method of
mounting, is you're obviously not restricted to just 26 letters, in the event that you
somehow have more than 26 storage devices. So say that you do, and you actually run out
of letters. What you could then do for example, is create a folder path in your main C drive,
call it something like 'mounted', then create as many folders as you want in there, and
then using the disk manager, link each of those folders to a different drive. And instead
of their paths beginning with a letter, they'd start with C:/mounted You might realize that
sounds awfully similar to how we just explained how Linux works, except again instead of beginning
with the C:/mounted, it's just /mounted/. That might make it a bit easier to understand
how the Linux system works, now that you've seen how it works in Windows. Alright, now I know we went a lot further
than the initial topic of the video about the A and B drives, but hopefully now you'll
have a much better understanding about how drive letters and drive mounting works in
Windows in general! So let me know what you think down in the comments. If you guys want to keep watching, the next
video I would definitely recommend everybody watch is one I made showing you how to become
a computer expert in under 15 minutes. Might sound like an exageration, but not really.
So you can just click that right here, thanks for watching, and I'll see you in the next
video.
