The remote variable resistor functions as a voltage-controlled resistor whose resistance changes based on an applied voltage.

Moving the position of the slider on this resistor, changes the length of wire in the circuit which changes the resistance. A variable resistor is used in some dimmer switches and volume controls ...

Circuit diagrams use symbols to represent these, ... different from a variable resistor, which adjusts current; Diodes. Image caption, Symbol and photo of a diode.