LPI Linux Essentials Certification All-in-One Exam Guide

I used this book alongside a couple of online courses and it was helpful. There was too much focus on PC hardware for my liking and some commands mentioned in this book didn't work for me at all (and I tried on a few different distros).

But overall not a bad experience. I liked the chapter reviews and there was plenty of practice questions. The ebook version on the disc came in handy as well and was a nice bonus.