Re: Linux isn't an operating system

Richard Stallman (
Wed, 6 Mar 1996 21:40:04 -0500

I learned to distinguish between an operating system and its kernel
while working at MIT, since before starting the GNU project. That is
why the GNU system is not the same as the GNU Hurd plus Mach.

I was surprised to learn that some people consider "operating system"
to be synonymous with "kernel". But they have quoted textbooks, so
this usage seems to be well established.

The other usage, which distinguishes the two terms, is also well
established. Here's what the Feb 1966 issue of Linux Journal says, on
page 7, in answer to the question "What is Linux?"

Linux itself is the kernel, the "core" of the operating system,
Most people use "Linux" to mean all of the software that goes along
with the kernel to make a usable operating system.

Many of the users of Linux have got their idea of the meaning of
"operating system" from there. That explanation distinguishes clearly
between the kernel and the whole collection of software you need to do
actual work, but it suggests calling them both "Linux".

So it appears that "operating system" is ambiguous. It can mean the
whole collection of system software, or it can mean just the kernel.
This ambiguity probably tends to encourage confusion between those two
different entities.

Most users who use Linux install whole collections of software, which
contain Linux. These collections include Slackware, Debian,
Plug-and-Play, RedHat, and so on. They are analogous to
non-Linux-based collections such as NetBSD, SunOS, HPUX, and Unix. We
can call such collections operating systems, or ready-to-use
self-sufficient software distributions, or some other term. Whatever
name we use, the difference between these collections and the kernel
is clear.

I call these collections "Linux-based GNU systems" to help promote
unity and cooperation in the whole community. I hope some of you will
join me in doing this.