When you're used to the world of Windows or OS X, Linux can seem a little unforgiving.
Not only does command-line access hand over the complete keys to the manor to any unwitting user with access to the administrator's account, there's rarely a safety net should things go wrong.
Despite advances in most Linux desktops (where the ubiquitous Trashcan safely buffers deleted files), you get no such protection from most system specific configuration, installation and maintenance tools.
And while it's rare for anything to go wrong without your direct input, some accidents do happen, especially if you enjoy tinkering with the latest distro release each month.
But this being Linux, there's plenty you can do to dig yourself out of a hole, which is why it's always a good idea to have a repair-worthy distribution close to hand when performing configuration and installation tasks.
One of the best developments in recent years has been the Live CD. These offer a fully functional Linux installation that runs from an optical drive. If you've got enough memory, you can even install new packages to the RAM disk just as you would when completing a standard installation.
This makes a recent release of a Live CD-based installer like Ubuntu Jaunty the perfect system recovery tool. Not only does it include every package you might require, but because it runs from the optical drive rather than the hard drive, your data isn't touched and there's no chance files will be overwritten without direct input. It's the obvious place to start when you get stuck.
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