There are those that say you should call a Linux kernel based Unix-like OS distribution GNU/Linux, because many contain a lot of GNU tools. I disagree, it is easy to replace 100% of the "GNU" foundation tools with ones that are completely Open Source (not GPL), thus getting rid of the GNU altogether, and still being able to run the same user mode software. So I argue that just like with AT&T Unix, BSD, Xenix, Solaris, etc the name of the OS belongs with the kernel not the other software that is easily replaced with different versions.

Many of those that argue to use the GNU naming will also attempt to argue that BSD is the only other widely used Open Source Operating System. This is blatantly not true. If you go by the argument that they use of the higher level tools contributing to the name of the OS, then there are many different Linux kernel based systems (not all are GNU), and then there are many other Unix likes. Though there are also non-Unix like OS's that are open source and widely used today. There are ReactOS, Haiku-OS, FreeMiNT (on Atari computers), MagiC, RISC OS, FreeDOS, AtheOS, Menuet OS, KolibriOS, SkyOS, GEOS, and many many more. Some may have started as closed source, though all these are now Open Source, and many started as Open Source, and every one of the ones listed has a significant size user base (that is to say should be considered to be widely used).

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