A friend of mine used to work on the development of the USB specification and subsequent implementation. One of the things that happens at these meetings is that hardware companies would show off the great USB hardware they were working on. It also gave them a chance to try out their hardware with various USB host manufacturers and operating systems to make sure everything worked properly together.
One of the earlier demonstrations was a company that was making USB floppy drives. The company representative talked about how well the drives were doing and mentioned that they make two versions, one for PCs and one for Macs.
“That’s strange,” the committee members thought to themselves. “Why are there separate PC and Mac versions? The specification is very careful to make sure that the same floppy drive works on both systems. You shouldn’t need to make two versions.”