Resistors are commonly referred to directly as resistors in daily life. It is a current limiting element that, when a resistor is connected to a circuit, the resistance value of the resistor is fixed, usually two pins. It can limit the amount of current passing through the branch it is connected to. A fixed resistor is one whose resistance cannot be changed. A variable resistance is called a potentiometer or variable resistor. The ideal resistor is linear, that is, the instantaneous current passing through the resistor is proportional to the applied instantaneous voltage. A variable resistor used for voltage division. On the exposed resistor, one to two movable metal contacts are tightly pressed. The contact position determines the resistance value between either end of the resistor and the contact. A two terminal device with a definite functional relationship between terminal voltage and current, reflecting the ability to convert electrical energy into other forms, represented by the letter R, in ohms. Actual devices such as light bulbs, heating wires, resistors, etc. can all be represented as resistor components. A two terminal electronic component made of resistive materials with a certain structural form that can limit the passage of current in a circuit. A fixed resistor is one whose resistance cannot be changed. A variable resistance is called a potentiometer or variable resistor. The ideal resistor is linear, that is, the instantaneous current passing through the resistor is proportional to the applied instantaneous voltage. Some special resistors, such as thermistors, varistors, and sensitive components, have a non-linear relationship between voltage and current. Resistors are the most widely used components in electronic circuits, usually forming different series based on power and resistance values for circuit designers to choose from. Resistors are mainly used in circuits to regulate and stabilize current and voltage, and can serve as diverters and voltage dividers, as well as circuit matching loads. According to circuit requirements, it can also be used for negative or positive feedback of amplification circuits, voltage current conversion, voltage or current protection components during input overload, and can form RC circuits as oscillation, filtering, bypass, differentiation, integration, and time constant components