Electricity and electronics are involved in the generation, transmission, and storage of power in numerous applications. The field of study in these topics is very large. The coverage here will be limited to a brief discussion of circuits and power flow. Electrical circuits are the interconnection of components for generating and distributing electrical power, converting electrical power to another form (such as light, heat, or motion), or processing information. Electrical circuits contain a source of electrical power, passive components, which dissipate or store energy, and active components, which change the amount of electrical power. Circuits can be broadly classified as direct current (DC) where currents and voltages do not vary with time, and as alternating current (AC) where currents and voltages vary with respect to time. There are several quantities used in electrical circuits: charge, current, voltage, energy, power, resistance, inductance, and capacitance. The two basic types of circuit connections, parallel and series. There are two tools used in analyzing simple electrical circuits. These tools are based on two conservative laws that govern the behavior of basic circuits: Kirchoff’s Loop Rule and Kirchoff’s Point Rule.