It's a labor of love and a great reference to go back to, but I wouldn't recommend it for newcomers.

Traditional books benefit from having an editor who (ideally) asks questions like "who are you writing for", "what's the best order to introduce ideas", and "how much detail is enough". If you don't ask these questions, you often end up getting too deep into the weeds or jumping back and forth between ideas in ways that can be difficult to follow. To give you a specific example, the guide spends a lot of time on some of the more obscure theories in DC network analysis before even defining what a battery is, capacitors and inductors are explained in the DC section by focusing on their AC characteristics, there is a ton of unnecessary quantum physics trivia ahead of explaining what a diode is, discussion of op-amps kicks off with an odd reference to calculus, etc.

Again, I don't mean that as a criticism, it's just that (properly edited) books have their merits.