All about Drive letters and drive names..

In the Windows world, drives can be identified by their names (such as "Windows7_OS") and their drive letters (such as "C:"). The important thing to remember is that Windows really only cares about the drive letter. That has to be unique; you can't have two drives labeled E: on the same computer.

The name, on the other hand, is just for convenience. Windows displays it and lets you edit it, but the OS doesn't use it when selecting which drive to access. That's why you can have two or more drives with the exact same name without confusing Windows.

Just for clarity, I'm using the word drive here to mean not a physical drive but a partition. Of course, if a physical drive has only one partition, it's effectively the same thing.

The drive letter plays an important role in telling Windows where to look. A file in C:\Users probably isn't also in D:\Users. The drive letter standard, with the colon (:), dates back to before DOS.

By default, in Windows (and in DOS before it), the boot drive is C:. Other drives, whether they're internal, external, optical, or additional partitions, get other letters, usually in the order they were assigned: D:, E:, and so on.

What about drives A: and B:? Their absence is a historical relic. Those letters were originally set aside for floppy drives.

Changing a drive letter can cause problems. For instance, if you've got a shortcut that points to a program installed on E:\, and you change drive E: to F:, the shortcut will not work.

To change a drive letter, click Start or go to Windows 8's Search charm. Type partitions (don't miss that s), and select Create and format hard disk partitions.

In the resulting Disk Management program, right-click the drive or partition you want to change, and select Change Drive Letter and Paths.

In the next dialog box, click Change.

This brings up yet another dialog box. Select an available drive letter and click OK.

A message box will pop up, warning you about the problems I discussed above. What you do here is up to you.

On the other hand, changing a drive name is safe and easy. In Windows 7 or Vista, click Start>Computer. In Windows 8, open File Explorer, and in the left pane, find and select This PC.

Once there, either press F2, or right-click and select Rename.

That's all there is to it.