To put electricity to work for us, we need to generate currentsCurrent of flowing chargesCharge in circuitsCircuit with components that are designed to convert electricElectric energyEnergy into thermal or mechanical energyEnergy. These circuitsCircuit come in many sizes. They can be miniature circuitsCircuit boards used in our microelectronicMicroelectronic gadgets or large generatorsGenerator powering heating and air conditioning systems. This chapter focuses on the analysis of electrical circuitsCircuit and their basic components. Some of the themes of the chapter are represented in Figs. 8.1, 8.2, 8.3 and 8.4. Figure 8.1 shows a typicle circuit board. Figure 8.2 shows a solonoid. Figure 8.3 shows a set of resistors. Figure 8.4 shows a pacemaker thatcontrols a human heart beat.