I guess I could have looked up fdisk. Thanks for overlooking my laziness.

Very enlightening about the C drive! I can respect extreme backward-compatibility, so I don't mind that they don't reclaim A or B. That said, the scheme is pretty stupid. I'm surprised it stuck around, but I guess once they'd made the decision, they just figured it was too late to change. It seems the more I learn about the historical Microsoft, the more I feel like it was started with no prior research, but then again maybe I'm biased because we live in such an open source world. After all, maybe back in the early 80s you couldn't just call up Bell Labs and ask if the way you're programming disk detection made sense or not.