Why Windows Starts at C:
The letters A and B weren’t skipped by accident. They were already assigned to the floppy-disk drives that came before hard drives became standard in personal computers.
Early PCs often had two floppy drives: one commonly held the disk that started the computer, and the other could hold a program or files. DOS, the operating system that preceded Windows on many PCs, identified those drives as A: and B:. Drive letters made it possible to refer to different storage devices with short, consistent names.
When the Hard Drive Arrived
A hard drive gave a computer much more room to store its operating system and programs, but DOS’s familiar drive-letter scheme already existed. The new storage device was assigned the next available letter: C:.
That convention persisted as Windows grew from a graphical layer on top of DOS into a modern operating system. Even after floppy drives largely disappeared, keeping the main Windows installation at C: preserved compatibility with software and scripts that expected it there.
The Letters Are Still Assignments
C: is not a special physical location inside a computer. Windows assigns letters to storage volumes—parts of a disk that the system treats as separate drives—and other letters can be used for additional volumes, removable drives, or network locations. A computer could, in principle, use a different letter for its main installation, but changing the convention can confuse programs that assume Windows lives at C:.
The old floppy drives are gone from most PCs; their place in the alphabet remains as a small legacy of how early computers organized storage.
