What you need for this book
To better understand this book, it is important that you have some previous background in some topics that are not covered or are just briefly mentioned along the text.
A basic understanding of the GNU/Linux environment usage and embedded Linux is important along with general concepts used in development as compilation, debugging, deployment, and installation. Some experience with Shell Script and Python is a bonus because these programming languages are core technologies used extensively by the Yocto Project's tools.
However, the concepts enumerated should not discourage you from reading this book as they can be learned concurrently.