İntroduction

In electronic circuits Copper, Aluminum materials are known as conductors, which are having negligible resistance. Other materials like paper, ceramic are known as insulators which are having very high resistance. Other materials like carbon with certain value of resistance are used to manufacture resistor. The value of resistance varies from very low to very high value, almost from the value of conductor to insulator. The value of resistanee is measured in ohms (Ω). Resistance is the opposition to the flow of electrons or simply opposition to the electric current. Resistance is required in electronic circuits to limit the current, to drop the voltage and to divide the voltage. In combination with capacitor it is used as filter or it can be used to achieve the time constant and so on. Hence resistor is one of the important component you can observe, in any particular circuit. Usually there are more number of resistors than any other type of components used in circuit.