The book is full of practical information. The main purpose isn't to teach you concepts (though they're in here). We've picked a lot of common problems and we'll show you how to solve them.
Even though it's not designed to be read in strict order, the book is organized into chapters with related subject matter. If you want to find a specific subject, the table of contents is still a good place to start. In addition, many of the chapters contain shaded boxes. These are like small tables of contents on a particular subject, which might be even more limited than the scope of the chapter itself. Use the Index when you're trying to find a specific piece of information instead of a general group of articles about a topic.