What is a Resistor
An electric resistor is a twoterminal passive component specifically used to oppose and limit current. A resistor works on the principle of Ohm’s Law which states that voltage across the terminals of a resistor is directly proportional to the current flowing through it.
Ohm’s Law: V = IR
where V is the voltage applied across resistor,
I is the current flowing through it,
and R is the constant called resistance.
The unit of resistance is ohms.
Types of Resistors

Fixed resistors

Carbon Composition Resistors

Carbon film resistors