What is resistor and formula of color code

Resistor: 

A Resistor is electronic passive device that resist to flow of electron through in it.

This is the short form to remember the color code-

B.B.R.O.Y.Good.Boy.Very.Good. Worker.

BBROY GOOD BOY VERY GOOD WORKER

B-Black----------------0

B-Brown------------1

R-Red--------------2

O-Orrange-------3

Y-Yellow-------.4

Good-Green- --5

Boy- Blue-------6

Very-Violet------7

Good- Gray-------8

Worker-White------9

Most of the resistor as usual   4 or 5 band. 

Lets two  resistor just look like this..................

first one after another band is for numeric value and before tolerance band  is for multiplier and last band for  tolerance. 

Green-5

Blue-6

Yellow-4 

So value for 1st resistor is - 56X10 power 4= 56X10^4=56X10000=560000 =560 Kilo ohm.

For Second resistor-

Red-2

Orange-3

violet-7

black-0

So value for second resistor is -237X10^0=237x1=237 ohm 

Tolerance value will be added with the total valve. which may addition or subtraction, which is clearly shown at the right side of the picture.