What does the absence of a color band on a resistor indicate?

The absence of a color band on a resistor typically indicates a tolerance of 20%. In resistor color coding, the tolerance is represented by the last band on a resistor. If there is no band present at all, signalizing that no tolerance value has been applied, the standard inference is that the resistor's tolerance is indeed 20%. This means that the actual resistance value could vary by 20% above or below the nominal value printed on the resistor.

It's important to understand the significance of tolerance in electronic components, as it indicates the variability one can expect in the performance of the resistor. A lower tolerance value generally denotes higher accuracy in resistance, while a higher tolerance value indicates more variability and less precision.