In this lab the student will analyze, build, and test a simple circuit with a resistor, a variable resistor or potentiometer, a light emitting diode (LED), and an independent source. By analysis, we mean that the student will predict the voltage across and current through branches in a specified electrical circuit. By building, we mean that the student will use a solderless breadboard to construct the specified circuit. By testing, we mean that the student will use a digital multi-meter (DMM) to measure the voltage across and current through various branches of the specified circuit. This section discusses some of the background material required to complete the lab.