This is a very basic book on electrical.The drawings showing electrical hookups are misleading because that's not how an electrician would wire.You don't go in and out of a receptacle with the hot and neutral on the receptacle itself; you pigtail. My fear is that some home owner will try and tackle these projects with no understanding of electrical theoryor on the job trainingThe difference between electrical and other trades is that if you make a mistake you could be dead or burn you're house down.