Classification of resistors
The resistor is a current-limiting element. Resistor is to provide a circuit to prevent the flow of current components, resistors through the consumption of electricity, the distribution of current in the circuit, so as to achieve a specific purpose.
Resistors can be divided into three categories:
(A) of the fixed resistor. It can be subdivided into winding resistance and non-winding resistance. Instead of winding resistance can be divided into:
 solid resistors
 Film resistors
 Glass glaze resistors.
(B) variable resistor. Can be divided into slippery wire resistors and adjustable line Rao resistor.
(C) sensitive resistors. Sensitive resistors are resistors that are sensitive to external factors such as temperature, voltage, humidity, light, gas, magnetic induction, and mechanical forces.