The book is divided into 15 chapters; first chapter provide the basic circuit analysis and theorems, second chapter is semiconductor diode, and this chapter gives as idea about the properties of semiconductor, conductor and insulator, including different types of diode, their properties and characteristic curves. Chapter three discuss about the power supply and different parts of it, fourth and fifth chapter deals with the bipolar and unipolar junction transistors. Sixth and seventh chapter is related to amplifier and their characteristics. Chapter eight gives an idea about feedback amplifier and its advantages. Chapter nine is related to oscillators. Chapter ten is devoted to operational amplifier, and eleven and twelve are related to digital circuits and K - map. Chapter thirteen and fourteen are related to modulation and demodulation. The last chapter of book deals with the CRO.