The book provides basic concepts about the elements of electrical and magnetic circuits. The physical processes occurring in these circuits are explained. The method of their calculation is described. The book contains basic information about electrostatics and electromagnetic induction, about the actions of electric current, direct and alternating current, about electrochemistry. The material is presented in a simple and accessible language using only the simplest mathematical apparatus. The book contains over 1000 figures, 340 numerical examples for calculations, 1200 tasks and 1000 self-test questions.