Resistor color codes
The value of a resistor is marked on its body using color bands. The majority of the resistors contain four bands but there are also some resistors that have five and six bands. The following picture shows what a resistor with four bands looks like:
With a four-band resistor the first two bands, from left to right, indicate the resistor's value. The third band is the multiplier and the fourth band is the tolerance. Resistors that have five bands use the first three bands to indicate the resistor's value, then the fourth band is the multiplier and the fifth band is the tolerance. The following table shows the color values:
The resistor pictured the beginning of this section has four bands coloured Yellow-Violet-Orange-Silver, which means the resistor is a 47K Ohm with 10% tolerance. We know this because the first two bands (Yellow and Violet) have values of 4 and 7. We then use the third band (Orange) as the multiplier which is 1K. This gives us a resistance value of 47 multiplied by 1K or 47K. The fourth band (Silver) indicates a tolerance of 10%.