If you're reading this chapter, you might be thinking, "Maybe I should try one of those other operating systems. But I sure would hate to completely remove Windows and lose all those custom features and options that I spent so much time organizing." The good news is that you can install two or more operating systems on a single computer, and choose the one you want to use each time you turn on the computer. The bad news is that the process is somewhat complex, especially if you don't already have a working knowledge of both operating systems, and the different file systems used by Windows and Unix or Linux can add to the confusion.
So it's generally better to dedicate a separate machine to the new operating system. Remember that Linux and any of the BSD Unix versions can run quite well on a system that Windows XP (let alone Windows Vista) would refuse to even consider. If you (or your friends or relatives) don't already have an old computer that you're no longer using, you can often find one very cheaply at a rummage sale or secondhand computer store. The whole thing, including a secondhand CRT monitor, keyboard, and mouse, and a network interface card shouldn't cost you more than about $50.
Any computer with an early Pentium processor should be entirely adequate to experiment with. If you can find an inexpensive additional memory module or two that fits your new old computer, go ahead and add them. When you decide to use the new OS for general use, you can add more memory and a bigger hard drive later.
For more information about how to add memory, see Chapter 7. Chapter 9 contains details about how to install hard drives.
If you decide to try setting up a dual boot system that can allow you to load more than one operating system on the same computer (one at a time), look for a specific procedure for the version of Unix you want to install alongside of Windows. Run a Web search for "howto dual boot xp [insert version here]" for instructions that apply to your particular choice of Unix or Linux versions.