A potentiometer is an electronic component that can be used to adjust the voltage within a circuit. They are commonly used in many different applications, including controlling the volume of an audio output or adjusting the brightness of a light. Potentiometers use a wiper that moves along a resistor to vary the resistance between two terminals. When the wiper is connected to one terminal, the resistance between the two terminals is low and when the wiper is connected to the other terminal, the resistance is high. When used in combination with resistors, capacitors, and other components, potentiometers can be used to create specific control circuits for a variety of applications.