Potentiometers comprise a resistive element, a sliding contact (wiper) that moves along the element, making good electrical contact with one part of it, electrical terminals at each end of the element, a mechanism that moves the wiper from one end to the other, and a housing containing the element and wiper.
Types of Potentiometer : Rotary, Single turn, Multi- turn (3 turns ,5 turns & 10 turns), Linear, Carbon pot - Volume control, Cermet, Conductive plastic, Wire wound, Trimpots, Servo Potentiometer.