A resistor is a two-terminal electronic component that produces a voltage drop across its terminals when subjected to an electric current. Its primary function is to oppose the flow of current in an electrical circuit. Resistors are classified according to their resistance value, which is expressed in ohms. The higher the resistance of a given resistor, the more it opposes the flow of current.
There are various types of resistors, each with its own unique set of characteristics. Fixed resistors have a fixed values, while variable resistors can be adjusted to alter the level of resistance they provide. Variable resistors are commonly used to control the volume levels in audio equipment.
