The three basic laws we will discuss are Ohm’s law, Kirchhoff’s voltage law, and Kirchhoff’s current law. The main terms used are voltage (units are Volts), current (units are Amps or milliamps), and resistance (units are ohms). These terms by themselves are meaningless unless a relationship can be established. An analogy that we can use to visualize the relationship between voltage, current and resistance is water flowing through a pipe. In the water analogy, pressure that pushes the water would correspond to voltage. The water flowing through the pipe would correspond to current. Any obstruction in the pipe restricting the flow would correspond to resistance