Overall this is a relatively comprehensive book.
(1) Conceptually explains the professional terminology related to ROS, which is relatively easy for beginners to understand the ins and outs;
(2) The following procedures are more difficult for people (such as me) who have less contact with programming (which is normal, because this is not a popular science programming book after all);
(3) ROS-related tools are introduced in more detail, such as rqt_console, rqt_logger_level, image_view, etc.;
(4) The following examples feel less universal, such as using game controllers, robotic arms, etc.;
Judging from this book, if you want to master ROS, programming basics are essential.
Below are some key screenshots.