Around 1990, Linus Torvalds, a Finlander, was a university student and couldn’t afford to purchase a copy of Unix. Doing what any good student does, he wrote his own kernel. On September 17, 1991, Linus released the first version of the Linux kernel. Instead of creating yet another proprietary software product, Linus made the Linux kernel a community software development effort.
Strictly speaking, the name Linux only applies to the kernel. The kernel is the core of the operating system, and provides services to both the hardware and to user applications. In the world of Linux, knowing the version of the kernel that you are running is like knowing the model of car that you are driving. Current versions of Linux run a version of the 2.6 kernel. For example, the latest release of the Fedora Linux kernel is based on the 2.6.22 kernel. You can always find out the version of the kernel by entering the command uname -r.
While the kernel does it job quietly in the background, you run applications from the command line for from a graphical environment. Many of the command line applications, including the C compiler, are part of the GNU project, which dates back to 1984. Richard Stallman create the Free Software Foundation 1985, and development the GNU General Public License (GPL). The GNU open source applications that were developed for Unix, were ported to Linux. Thus, Linux has a definite Unix-like touch and feel. Using the GPL license as a foundation, different communities developed and maintain different software products, such as Gnome, KDE, OpenOffice, and 1,000’s of other products. The latest release of Debian Linux comes with over 18,000 software packages.
It is the packaging of all the products into a installable product that makes a distribution of Linux. Like everything else in Linux, if I don’t like what is out there, I can create my own distribution. Yet, everything is bound together by the common Linux kernel and the community nature of the software applications. The major distributions of Linux are as follows:
- Red Hat Linux / Fedora — One of the three major distributions of Linux, Red Hat sells Red Hat Enterprise Linux (RHEL), and sponsors the Fedora Project. The Fedora Project is the free, open source, and leading edge edition. You can download the latest version of Fedora by following the links from http://fedoraproject.org. Be aware, Fedora is the lead developer in Secured Enabled Linux (SELinux). Unless you are ready for extreme security, you need to disable SELinux during the installation. All distros support SELinux, only Fedora makes it a big deal. The default desktop is Gnome.
- SUSE Linux — Now owned by Novell, SUSE Linux has and enterprise edition (SLED) and a pure open source edition called openSUSE. SUSE Linux is one of the easiest to install. It uses the KDE (K Desktop Environment, because K is one less than L) graphical desktop, and the kernel includes the AX.25 drivers for amateur radio. You can download the latest version from www.opensuse.org. You can also purchase a boxed edition from Novell.
- Debian Linux — Debian is a community project, and emphasizes free software. Version 4.0 comes on three DVDs, and sport 18,000 plus applications. It has the largest collection of ham applications of any distribution. Debian is not as fancy as Fedora or SUSE, but it is an excellent edition with a default Gnome desktop. In the crazy world of open source, the Firefox browser is IceWeasel in Debian, and Thunderbird is IceDove.
- Knoppix Linux — The first Live CD (now DVD) edition of Linux. Live CD editions are a great way to explore Linux without having to install it. If you want to keep any changes you will need space on your disk, or memory stick. Knoppix is my favorite Live DVD version. It is based on Debian Linux.
- Ubuntu — Ubuntu is another Live DVD version of Linux, and is also based on Debian Linux. You can install Ubuntu, but it assumes that it is the only version of Linux on the machine. Ubuntu comes in a other flavors (Kubuntu and Xubuntu).
The above was a short list of Linux distributions (distros, in Linux speak). You can find a complete list at http://en.wikipedia.org/wiki/List_of_Linux_distributions. If you are like me, downloading multiple gigabytes is tedious. You can purchase CD and DVDs from a number of sources. I use www.linuxonline.biz, or www.discountlinuxdvd.com. You can stock up on a half dozen distros for less than $20, including shipping.