Amazon offers Linux for Beginners: An Introduction to the Linux Operating System and Command Line for FREE. For comparison, it regularly sells for $20+ as a paperback. This is a great way to learn about Linux and the code behind it. Rated 4.4/5 stars.
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Knowing where to start when learning a new skill can be a challenge, especially when the topic seems so vast. There can be so much information available that you can’t even decide where to start. Or worse, you start down the path of learning and quickly discover too many concepts, commands, and nuances that aren’t explained. This kind of experience is frustrating and leaves you with more questions than answers. Jason Cannon has been a professional Unix and Linux System Engineer since 1999. During that time he has worked in a wide variety of environments ranging from small, fast-paced organizations to large, well-established corporations. He enjoys teaching others how to use and exploit the power of the Linux operating system.