We know that the resistor colour code markings are always read one band at a time starting from the left to the right, with the larger width tolerance band oriented to the right side indicating its tolerance.
Color codes are mainly used to identify the resistor's value. Components and wires are coded are with colors to identify their value and function.
The colors brown, red, green, blue, and violet are used as tolerance codes on 5-band resistors only. All 5-band resistors use a colored tolerance band. The blank (20%) “band” is only used with the “4-band” code (3 colored bands + a blank “band”).
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