Types of Resistors Resistors come in a variety of values and types. The most common type is the fixed resistor. Fixed resistors have single values of resistance, which remain constant. There are also variable resistors that can be adjusted to vary or change the amount of resistance in a circuit. The value of resistance of resistors is given in ohms.
Resistors can have values from less than one ohm up to many millions of ohms.
The most common fixed resistor is the composition type. The resistance element is made of graphite, or some other form of carbon, and alloy materials. These resistors generally have resistance values that range from 0.1 W to 22 M W . Another kind of fixed resistor is the wire wound type. The resistance element is usually made of nickel-chromium wire wound on a ceramic rod.