A resistor is a passive two-terminal electrical component that resists the flow of electrons as a circuit element. The current through a resistor is in direct proportion to the voltage across the resistor's terminals. This relationship is represented by an alternative representation of Ohm's law, which yields the current I as the ratio of the potential difference V to the resistance R:
The symbol used for a resistor in a circuit diagram varies from standard to standard and one country to another:
In the real world, a typical axial lead carbon resistor will look like this:
The value of the resistor can be measured by using the color code marked on them. The color bands of carbon resistors can be four, five, or six bands.
The first two...