Resistance colour code

Resistors are the electrical element which restrict the flow of electric current, for example a resistor is placed in series with a light-emitting diode (LED) to limit the current passing through the LED.Resistance is measured in ohms, the symbol for ohm is an omega . 1  is quite small equal to 1volt/1 ampere. So resistor values are often given in k and M. 
1 k = 1000      1 M = 1000000 .

Resistors we use generally are very small in size and to write its value with precision accuracy percentage is not a mind job so these are represented using coloured bands. 

generally there are two types of resister (4 Band and 5 Band), whose value can be calculated using the following diagram....

In a 4 Band resistor..

• The first band gives the first digit.
• The second band gives the second digit.
• The third band indicates the number of zeros.
• The fourth band is used to shows the tolerance (precision) of the resistor.

Thus for the above 4 Band resistor's value can be calculated as

 56(represented by green and blue band in first and second position) ×10k(represented by yellow band) =560k.

And its percentage tolerance is +-5%(represented by golden band).

In a 5 Band coded resistor..

• The first band gives the first digit.
• The second band gives the second digit.
• The third band gives the third digit.
• The fourth band indicates the number of zeros.
• The fifth band is used to shows the tolerance (precision) of the resistor.

Thus for the above 5 Band resistor's value can be calculated as

 237(represented by red, orange and voilet band in first, second and third position) × 1(represented by black band) =560k.

And its percentage tolerance is +-1%(represented by brown band).

Thanks hope this was some useful stuff for many resistance application related purpose.