Users who don't want to build an entire Linux system from scratch probably don't want to read this book. If you, however, do want to learn more about what happens behind the scenes, in particular what happens between turning on your computer and seeing the command prompt, you want to read the "From Power Up To Bash Prompt" (P2B) HOWTO. This HOWTO builds a bare system, in a similar way as this book does, but it focusses more on just installing a bootable system instead of a complete system.
To decide whether you want to read this book or the P2B HOWTO, you could ask yourself this question: Is my main objective to get a working Linux system that I'm going to build myself and along the way learn and learn what every component of a system is for, or is just the learning part your main objective. If you want to build and learn, read this book. If you just want to learn, then the P2B HOWTO is probably better material to read.
The "From Power Up To Bash Prompt" HOWTO can be downloaded from http://www.netspace.net.au/~gok/power2bash/