RESISTORS, How are they made? There are many different types of resistors used in electronics Each type is made from different materials Resistors are also made to handle different amounts of electrical power Some resistors may change their value when voltages are placed across them These are called voltage dependent resistors or nonlinear resistors. Most resistors are designed to change their value when the temperature of the resistor changes. Some resistors are also made with a control attached that allows the user to mechanically change the resistance. These are called variable resistors or potentiometers. Figure 2 shows physical shapes of some different types of resistors.