When you think of the PowerPC processor, chances are you’ll think of just two platforms and, by association, two operating systems. Apple’s Mac OS X, which runs on Apple’s own hardware, and the AIX Unix operating system from IBM, which runs on their own PowerPC platform systems. In reality, there is a wide choice of potential operating systems that work on a wide range of PowerPC platforms. If you want a Unix-like alternative to AIX, particularly a free software one, then Linux seems the obvious choice, but there are others.