Linux systems that run directly from the CD are very popular. These live distributions not only help attract new users to the world of Linux but are useful if you need to repair a broken system. When something breaks, you might find yourself in a situation where the tool you need for the repairs is not available on the CD. If you have been through this before, you will be familiar with unresolved dependencies and missing libraries on read-only filesystems. Even if you manage to install the tool, it might just die despite all your efforts. And users often want to try out new programs on production systems without having to go through a global install.

The Klik project makes all these dreams come true. Klik is short for "KDE-based Live Installer for Knoppix+Kanotix." Its makers have adopted the bundle design made so popular by Apple. Bundles are typically special, compressed archives containing all the files and libraries required by an application along with some metadata. To install, users simply download the archive file off the Internet and drop it on their desktops; the operating system launches the application stored in the archive. The system hides the processes from the user (Figure 1). As there is no need for a complicated and time-consuming install, and no need to spread files all over the filesystem tree, you can even install different versions of the same program. The basic Linux system is untouched. And you can dock applications stored on USB sticks to make them available to a live distribution.