Do you know where electricity comes from? To be able to say yes to that question, you must understand a bit about the physics of matter. What value does a brief study of the nature of matter have for the student of electrical theory? The understanding that comes from that study lays the foundation for understanding electrical theory. Only when you know the theory can you truly have confidence in the practical aspects of your electrical work. This full-color textbook provides hundreds of illustrated graphics, detailed examples, practice questions, practice exams, summaries and a comprehensive practice final exam.