It truthfully took me quite awhile to get through this, in part because I had several other RPi3 books I was reading as well as the fact that I always bite off more than I can chew and read far too many books simultaneously. Goodreads states I'm in the middle of 200 right now, which isn't quite accurate, because I've finished a couple of dozen and need to update those and even when I'm reading a ton, usually I'm just focusing largely on a smaller core group of 30-40 while leaving the others unread for 4-5 days, so it takes me forever to get through books. I read a few chapters, go to the next one and repeat, go to the next one and repeat, etc. My problem is I have numerous interests and I'm always finding really intriguing books to read. Anyway, I had already read about four RPi books -- much smaller -- over the past couple of years and waited to this one last, and since it's nearly 800 pages, it was easier to rip through a bunch of 300 page books while slowly going through this and other larger ones. But I was seriously impressed with this book! It was easily the most comprehensive, well written and extremely good book I've found on RPis or Arduinos and it answered a lot of questions none of the other books did, and in a user-friendly way. So if you're going to start exploring RPis, this is a great investment and resource and hence, it's recommended!