Uh, “a PC” and “a Mac” are hardware platforms. Linux is an operating system kernel. I do not understand this: you run Linux, usually, *on a PC* – but you can tun it *on a Mac* and other hardware too. IF (and only if) the original Apple-ad said “I’m Windows” and “I’m Mac OS”, THEN the addition “I’m Linux” would have made sense. Now it doesn’t.