The potentiometer, also known as a pot, is a variable resistor. A potentiometer allows for the creation of a circuit where the user can change the resistance. Potentiometer comes in various shapes, sizes, and values but they all have three connectors. The resistance between the two outer connectors is fixed and is the maximum resistance of the potentiometer. The resistance between the center connector and either outer connection various as the user turns the knob.
The potentiometer has lots of usages including audio control, motion control for servo motors and control brightness of a light.