Learn to Code HTML and CSS: Develop and Style Websites is exactly what it says on the tin: a book that teaches you how to craft websites with HTML/CSS. In terms of content, it's not that much different from Shay Howe's site, but it's a nicely condensed version of the same content - and one that you can take with you offline.
What this book does a great job of (and why I prefer it to Duckett's HTML and CSS book), is that the content is relevant and updated, provides a lot of useful tips for beginners, and focuses on best practices and semantic markup. It doesn't gloss over the important of HTML5 semantic elements, and it gives one of the better overviews of it in my opinion (ex: actually describing the difference between vs instead of saying 'use ').
Will update this review further once I finish the book, but at the moment I can stay it's a good, comprehensive overview of HTML & CSS. And for the most part, it boils down to the basics enough that most of the information hasn't become outdated.