An anonymous reader writes "Here is a free interactive beta of Learn Linux The Hard Way; a web-based virtual Linux environment which introduces the command line and other essential Linux concepts in 30 exercises. It's written in the style of Zed A. Shaw's Learn Code the Hard Way lessons. The authors says, 'You will encounter many detailed tables containing lists of many fields. You may think you do not need most of this information, but what I am trying to do here is to teach you the right way to approach all this scary data. And this right way is to interpret this data as mathematical formulas, where every single symbol has its meaning.' Of course, my first entry was rm -rf /* which only produced a stream of errors. I wish I had discovered something like a long time ago."