Slackware Linux Basics - Huihoo

Chapter 2. An introduction to
Slackware Linux
2.1. What is Linux?
Linux is a UNIX-like kernel, which is written by Linus Torvalds and other developers. Linux runs on many different
architectures, for example on IA32, IA64, Alpha, m68k, SPARC and PowerPC machines. The latest kernel and
information about the Linux kernel can be found on the Linux kernel website: http://www.kernel.org.
The Linux kernel is often confused with the GNU/Linux operating system. Linux is only a kernel, not a complete
operating system. GNU/Linux consists of the GNU operating system with the Linux kernel. The following section
gives a more extensive description of GNU/Linux.
2.2. What is GNU/Linux?
In 1984 Richard Stallman started an ambitious project with the goal to write a free UNIX-like operating system. The
name of this system is GNU, which is an acronym of “GNU's Not UNIX”. Around 1990, all major components of
the GNU operating system were written, except the kernel. Two years earlier, in 1988, it was decided that the GNU
project would use the Mach 3.0 microkernel as the foundation of its kernel. However, it took until 1991 for Mach 3.0
to be released under a free software license. In the the same year Linus Torvalds started to fill the kernel gap in the
GNU system by writing the Linux kernel. GNU/Linux thus refers to a GNU system running with the Linux kernel.
The GNU kernel, named “HURD” was still under development when this book was written, and is available as the
GNU/HURD operating system. There are some other kernels that are ported to the GNU operating system as well. For
instance, the Debian project has developed a version of the GNU operating system that works with the NetBSD kernel.
2.3. What is Slackware Linux?
Slackware Linux is a GNU/Linux distribution, which is maintained and developed by Patrick Volkerding. A
distribution is a coherent collection of software that provides a usable GNU/Linux system. Volkerding started using
GNU/Linux because he needed a LISP interpreter for a project. At the time the dominant GNU/Linux distribution was
Softlanding System Linux (SLS Linux). Slackware Linux started out as a private collection of Volkerding's patches
for SLS Linux. The first publicly available Slackware Linux release was 1.0, which was released on July 16, 1993.
In contrast to many other GNU/Linux distributions, Slackware Linux adheres to the so-called KISS (Keep It Simple
Stupid) principle. This means that Slackware Linux does not have complex graphical tools to configure the system. As
a result the learning curve of Slackware Linux can be high for inexperienced GNU/Linux users, but it provides more
transparency and flexibility. Besides that you get a deeper understanding of GNU/Linux with no-frills distributions
like Slackware Linux.
Another distinguishing aspect of Slackware Linux, that also “complies” with the KISS principle, is the Slackware
Linux package manager. Slackware Linux does not have a complex package manager like RPM or dpkg. Packages are
normal tgz (tar/gzip) files, often with an additional installation script and a package description file. For novice users
tgz is much more powerful than RPM, and avoids dependency problems. Another widely known feature of Slackware
Linux is its initialization scripts. In contrast to most other GNU/Linux distributions Slackware Linux does not have a
directory for each runlevel with symbolic links to services that have to be started or killed in that runlevel. It uses a
simpler approach in which you can enable or disable services by twiddling the executable bit of an initialization script.
The packages in Slackware Linux are compiled with as little modifications as possible. This means you can use most
general GNU/Linux documentation.
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