Windows typically assigns your system drive the letter C: and gives different letters to other storage devices. That’s unusual—macOS and Linux don’t use letters. Windows can access drives without letters, so why does it use them?
Where Do Drive Letters Come From?
Like many things in Windows—such as, how it uses backward instead of forward slashes—drive letters date back to the days of MS-DOS (in fact, even a bit earlier). This is the reason the Windows system drive uses the letter C:—A: and B: were reserved for floppy disk drives.
Drive letters were carried over to MS-DOS from CP/M, an older operating system. They offered a way to access logical and physical storage devices containing files. To access a file named README.TXT on the second floppy disk drive, you’d just type B:README.TXT.
The need for drive letters is apparent on the command line. If there were no drive letters, how would you quickly specify paths to files on different devices? This was the system MS-DOS inherited, and Microsoft has stuck with it since.
While drive letters might seem less important now that we’re using graphical desktops and can simply click on icons, they do still matter. Even if you only access your files through graphical tools, the programs you use have to refer to those files with a file path in the background—and they use drive letters to do so.
RELATED: Why Windows Uses Backslashes and Everything Else Uses Forward Slashes
The Unix Alternative: Mount Points
Drive letters aren’t the only possible solution, however. Apple’s macOS, Linux, and other Unix-like operating systems use a different method of accessing different partitions and storage devices.
