Pyrofan, sourcejedi is right. Linux is the name of a very good FLOSS kernel. OS distributions that combine the GNU system with the Linux kernel are more accurately referred to as GNU/Linux (but Debian is the only mainstream distro that does so); however, as sourcejedi pointed out, "Linux" is used more commonly. Let's not make this thread a debate about which is the correct name. I just wanted to explain why I kept saying "GNU/Linux". I don't mind if you want to call it differently.

sourcejedi, my first Mac ran Mac OS X, so I wouldn't consider myself a longtime member of the Mac community. Wikipedia's article on Mac OS refers to both Classic and Mac OS X, so I guess you're right (although Wikipedia also goes by "Linux" as the OS in most of its articles). If virtually no ones uses classic Mac OS, however, wouldn't it make sense for the OP to rename Mac OS to Mac OS X so that there will be no confusion?

BTW, I just want to throw this out there: I refer to both free software and open source software as FLOSS (free/libre/open source software) to avoid offending anyone (primarily RMS or ESR). GNU/Linux on the other hand makes more sense to me because it's basically the GNU OS with the Linux kernel (since Hurd took a bit too long to make :p). Sure you can install KDE or TeX and its higher-level document markup languages like LaTeX, but the core components of the system and what really defines the OS tend to come from the GNU project.

Ynot, getting back to the focus of this thread (or at least my original post), please add FreeBSD to the list.