Resistors, color code

I will explain how to know the value of the resistance of a resistor with color code.

A resistor is an electronic component that regulates the flow of electrical current in an electronic circuit. 

 In this photo you can see a resistor. As you can see, in the non-metal part (in this case wood) there's four colored bands painted. Each band has a meaning:
 - First band is the first number on the left.
 - Second band is the second number on the right
 - Third  band represents de number of zeros on the right
 - Fourth band is the tolerance of the resistor.

Here is a table that explain the color code and their value:

Example: Calculate the resistance of the resistor showed in the first photo.


 - First color is brown, so first number is 1
 - Second color is black, so second number is 0
 - Third color is green, so it has 10^5 zeros
 - Fourth color is gold, so it's tolerance is +-5

So, the resistance is 1000000 ohms = 1000 kiloohms