I discovered Linux in 1999 while working for two commercial distributions. As a product manager, at first I was mostly concerned with half a dozen potential business rivals. However, I quickly discovered that there was much more to Linux. Accustomed to Windows and OS/2, I struggled to grasp the idea that distributions – versions of Linux each customized for particular purposes – could even exist. But I soon learned that despite pundits' claims, Linux's diversity was a strength rather than weakness. Like many new users, I began to distro-hop, and the pleasure of discovery never entirely left me. A few years ago, when given the chance to write the Distro Walk column, I was happy to be paid for what I was already doing.

Still, I realize that the sheer number of distributions can be overwhelming for anyone starting to explore. After all, even developers can be daunted by all these distributions, mistakenly believing that they need to develop products for each distribution separately. Because this is my last column, I thought it might be useful to classify the main categories of currently active distributions. Some distributions fall into more than one category with various flavors, but overall the effort gives a broadly accurate picture of how rich and varied the whole range of distributions can be.

Core Distros

Core distributions function as the source of all derivatives. They are often among the oldest distros. While some older distros such as Slackware or Mandriva have fallen out of fashion in recent years, they continue to exist (in Mandriva's case, under the names of openMandriva and Mageia). Today, the major core distributions are Arch Linux, Fedora, and Debian.

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