Amazon has a variety of coding-related ebooks on sale for free right now. Most of these sold for as much as $3 to $5 recently, so being able to grab them for free is a no-brainer. This Python Programming for Beginners will help you learn how to get Python installed, understand the various ways to run it on Windows, Mac, and much more.

Linux for Beginners can teach you the differences between all the versions, how to set up a Linux server, what SSH is, and plenty of other stuff. Command Line Kung Fu will make you an expert in navigating commands to quickly and easily repeat commands in your shell history, strip out blank lines and comments from files, and more.

Lastly, Shell Scripting: How to Automate Command Line Tasks Using Bash Scripting and Shell Programming provides step-by-step process of writing shell scripts that solve real-world problems, how to quickly find and fix the most shell scripting errors, and lots of other useful information.

You can't go wrong with picking up any, or all, of these books, but be sure to do so before the discount ends. Don't forget, you can read Kindle books on a wide variety of devices including your PC, phone, or tablet.