What is a C drive?

Answer: In Windows, disk drives are identified by letters. These include hard drives, floppy disk drives, optical drives and hard disk partitions. Each drive or partition is assigned a letter, such as A, B, or C.

Since the letter-naming scheme dates back to the early days of DOS, the letters A and B are reserved for floppy disk drives 1 and 2. The C drive is then assigned to the main hard disk partition that contains the operating system and system files. The letters D through Z can be assigned to other hard drives, optical drives, flash drives, etc.

The technically correct way to refer to a specific drive on a Windows computer is with a letter followed by a colon. Therefore, the main hard drive on a Windows computer would be identified as "C:". You may also see the C drive represented as "C:\", in which case the backslash represents the root directory of the drive. This may appear in the address field of Windows Explorer or in the DOS command prompt. Any time you see a directory path that begins with "C:\", it indicates the file or folder is located in the system's primary hard drive.

Published: January 7, 2009 — by Per Christensson