This section used to be called Linux. But I didn't want to scare potential readers. You'll need a good Linux operating system on your machine to try most of the topics, but it's much easier to install than when I first tried it. Download and install a good linux distro, and you'll find that you've got a lot more than just an operating system. Office applications, media players, programming tools, Database management systems, internet applications, some very clunky games, lots of educational software and before you know it, you'll have forgotten what its like to pay for software