All branches of electrical engineering, it is based on two basic theories, namely, the theory of electrical circuits and the theory of electromagnetics. The theory of electric circuits includes many branches of electrical engineering, such as power, electric machines, control, electronics, communication, and instrumentation. Therefore, the subject "Fundamentals of Circuit Theory" is one of the most important subjects for students studying electrical engineering and is the starting point for mastering specialty subjects. Students also learn how to analyze electrical circuits including energy, charge, voltage, current, resistance, Ohm's Law, Kirchhoff's Law, DC and AC, RC, RL and RLC circuits as they master the science.