Then we'll add in a little history lesson, shall we? PC has long been used as an abbreviation for "Personal Computer", but it wasn't a very well-used phrase for many years - most people in the early 80s and before would've referred to a "micro" or "microcomputer" for this type of machine. And then IBM introduced their first model - the IBM 5150 or Personal Computer - PC was actually the product name, and one that was retained for several generations (PC XT and AT). It gained considerable market share, and before long everyone was trying to make IBM-compatible or "PC-compatible" machines. And so the usage changed from being any generic microcomputer to being specifically one with the same architecture as IBM and capable of running the same versions of DOS and later Windows. As time went by, the architecture and operating system defined the words more than IBM did, and when Macs became a lot more popular, the usage began to drift back to what it originally was - replacing micro for ever in common use. So the reality is that everyone's right - it's specific to IBM, it relates to Windows PCs particularly, it relates to the architecture so whatever operating system runs on it is unimportant, and it's a generic term for, well, a personal computer. The only thing that matters is that people understand which sense you mean it in.