Not worth reading! Go directly to documentation. Even the author is not talented in writing, so you will get bored of his writing style after dozen pages. He also doesn't explain technical points well, he just kept listing the features without any valuable description as if it was being automatically generated -to be included in the book- by a robot or some script. For few pages, I get convinced that he is not a technical guy who has practical experience, but later after checking who he is, I changed my mind (not totally). Also the book has a lot of copied sections and samples from Bootstrap's documentation, I think the author preferred to copy/paste the documentation instead of showing real life examples to save his time! In my opinion, this book was a "task" on him that he must accomplish, not no more than this; And I think he succeeded to finish it. For you, just use the documentation, or search for a better book which covers this topic.