A book can be helpful for other reasons. For a programming book, beginners especially may benefit from a linear structure that covers a predefined amount of content.

For example, you can go from zero rails experience to being able to build a site with Michael Hartl’s rails book. As a reader you can stay focused on the book and roughly assume you can understand Chapter 2 with the information from Chapter 1.

Conversely, a common complaint about intermediate-level Haskell is a lot of it is scattered across blog posts, and is difficult for beginners to follow.