There is no universal definition of the word "small" when it is used to define a Linux distribution. For some users, a small distribution is one that has a minimal footprint on a computer's resources. For others, a small distribution is the one that is distributed in a nifty little package and can be lugged around in a portable USB key. Both types of distributions have their uses. Small-footprint distros help save old and resource-strapped computers from ending up in a landfill, while USB-style distros give their users a safe, secure, and private environment on a public computer, like in a library or hotel lobby. The candidates we've selected in this article do a bit of both (see also the "Not Considered" box).

A lot of hardware is good enough to run the mainstream Linux distributions without any issues. However, the modern Linux desktop is a fairly resource hungry beast as well. Coupled with the fact that mainstream Linux distros are designed to appeal to a large number of users, they also have become too bloated. This has fueled the demand for lightweight options both for individual apps (see box titled "Lightweight Apps") and for complete distributions.

Just as it is difficult to define a distro as "small," defining hardware as "older" is also tricky. In addition to users who have hardware that's been outdated fairly recently, there's another kind who are holding on to their workhorses from the last decade. They usually just use their computer to browse the web, do some text editing, and watch some videos. It's a shame to force these users to dump their trusted machines and get the latest multicore computers loaded with several gigabytes of RAM or even a dedicated graphics card. However, chances are their workhorse isn't supported by the latest kernel, which keeps dropping support for older hardware that is no longer in vogue.

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