which is available in both source code and binary form. Its copyright is owned by Linus Torvalds
<
[email protected]> and other contributors, and is freely redistributable under the terms of the
GNU General Public License (GPL). A copy of the GPL is included with the Linux source; you can
also get a copy from ftp://prep.ai.mit.edu/pub/gnu/COPYING Linux, per se, is only the kernel of the
operating system, the part that controls hardware, manages files, separates processes, and so forth.
There are several combinations of Linux with sets of utilities and applications to form a complete
operating system. Each of these combinations is called a distribution of Linux. The word Linux,
though it in its strictest form refers specifically to the kernel, is also widely and correctly to refer to an
entire operating system built around the Linux kernel. For a list and brief discription of various
distributions, see http://sunsite.unc.edu/LDP/HOWTO/Distribution−HOWTO.html None of these
distributions is ``the official Linux''. Linux is not public domain, nor is it `shareware'. It is `free'
software, commonly called freeware or Open Source Software[tm] (see http://www.opensource.org),
and you may give away or sell copies, but you must include the source code or make it available in
the same way as any binaries you give or sell. If you distribute any modifications, you are legally
bound to distribute the source for those modifications. See the GNU General Public License for
details. Linux is still free as of version 2.0, and will continue to be free. Because of the nature of the
GPL to which Linux is subject, it would be illegal for it to be made not free. Note carefully: the `free'
part involves access to the source code rather than money; it is perfectly legal to charge money for
distributing Linux, so long as you also distribute the source code. This is a generalization; if you want
the fine points, read the GPL. Linux runs on 386/486/Pentium machines with ISA, EISA, PCI and
VLB busses. MCA (IBM's proprietary bus) is not well−supported in 2.0.x and earlier versions, but
support has been added to the current development tree, 2.1.x. If you are interested, see
http://glycerine.itsmm.uni.edu/mca There is a port to multiple Motorola 680x0 platforms (currently
running on some Amigas, Ataris, and VME machines), which now works quite well. It requires a
68020 with an MMU, a 68030, 68040, or a 68060, and also requires an FPU. Networking and X now
work. See news:comp.os.linux.m68k Linux runs well on DEC's Alpha CPU, currently supporting the
"Jensen", "NoName", "Cabriolet", "Universal Desktop Box" (better known as the Multia), and many
other platforms. For more information, see http://www.azstarnet.com/~axplinux/FAQ.html Linux runs
well on Sun SPARCs; most sun4c, sun4m, and sun4u machines now run Linux, with support for sun4
in development. Red Hat Linux is (as of this writing) the only Linux distribution available for
SPARCs; see http://www.redhat.com/support/docs/rhl−sparc/ Linux is being actively ported to the
PowerPC architecture, including PowerMac (Nubus and PCI), Motorola, IBM, and Be machines. See
http://www.cs.nmt.edu/~linuxppc/ and http://www.linuxppc.org/ Ports to other machines, including
MIPS (see http://linus.linux.sgi.com and http://lena.fnet.fr/) and ARM, are under way and showing
various amounts of progress. Don't hold your breath, but if you are interested and able to contribute,
you may well find other developers who wish to work with you. Linux is no longer considered to be
in beta testing, as version 1.0 was released on March 14, 1994. There are still bugs in the system, and
new bugs will creep up and be fixed as time goes on. Because Linux follows the ``open development
model'', all new versions will be released to the public, whether or not they are considered
``production quality''. However, in order to help people tell whether they are getting a stable version
or not, the following scheme has been implemented: Versions n.x.y, where x is an even number, are
stable versions, and only bug fixes will be applied as y is incremented. So from version 1.2.2 to 1.2.3,
there were only bug fixes, and no new features. Versions n.x.y, where x is an odd number, are
beta−quality releases for developers only, and may be unstable and may crash, and are having new
features added to them all the time. >From time to time, as the currect development kernel stabilizes,
it will be frozen as the new ``stable'' kernel, and development will continue on a new development
version of the kernel. Note that most releases of the Linux kernel, beta or not, are relatively robust;
``stable'' in this context means ``slow to change'' in addition to ``robust''. The current stable version is
2.0.35 (this will continue to change as new device drivers get added and bugs fixed), and development
has also started on the experimental 2.1.x kernels. The Linux kernel source code contains a file,
Documentation/Changes, which explains changes that you should be aware of when upgrading from
Linux Dictionary
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