Docker: A Project-Based Approach to Learning

As other have noted, there are errors and omissions in the book. In the first chapter where you install Docker he has you run a bunch of commands as root and then a "docker version" to make sure you have things setup. But he forgot to mention that you need to add you non-root user to the docker group to not get error messages on every following command run as a normal user.This book did get me jump started but it was 5 chapters in before I was told what Docker was for! What problem it might solve. Why my project might be using it and forcing me to learn something new.Also a page fell out of the book. If more fall out, the book will have to be returned.Edit: Lack of an index is a show stopper. Now that I can do minimal stuff, I find I need more of a reference book. The information I need is in the book, but without an index it is not possible to get to it. Dropping to 2 stars.