How to Understand Why the First Windows Drive Is Called C:

While the alphabet starts with the letter A, the first drive you encounter on a modern Windows computer is designated as “C:”. But what’s the reasoning behind this?

Contrary to popular belief, the designation of the first drive in Windows being “C” isn’t due to the operating system’s connection to the C programming language. Although C remains a significant language, particularly for system-level programming, its relevance to drive labeling is coincidental. In the Unix ecosystem, parts of the OS have historically been developed in C, but this influence doesn’t carry over to how Windows assigns drive letters.

Understanding the Sequence Behind the C Drive:

In the early era of personal computing, built-in storage devices like hard drives or SSDs weren’t standard; floppy disks served as the primary storage mediums, available in 5.25-inch and 3.5-inch formats. The floppy disk drive was allocated the letter “A:”, while the second disk drive was labeled “B:”. When the first internal hard drives emerged, Microsoft appropriately began labeling them with the next available letter—“C:”.

The Vanishing of A: and B:

So, why don’t we encounter the drive letters “A:” and “B:” on our contemporary computers? The answer lies in the fact that most modern systems do not include floppy disk drives anymore. These designations are permanently reserved for floppy drives, rendering them absent from the standard Windows drive list.

Following the letter “C”, Microsoft continued to assign drive letters sequentially in alphabetical order. A CD or DVD drive, which has also become less common, received the letter “D:”, while an additional hard drive would appear as “D:” if one was installed. Any new USB flash drives or additional hard disks are assigned “E:”, “F:”, and beyond, as users continue to expand their storage options.