Decode a 4-band resistor color code into its resistance value and tolerance.
Bands 1 and 2 are the two significant digits of the resistance value — for example Brown-Black reads as digits 1 and 0, giving "10" before the multiplier is applied.
It scales the two-digit number by a power of 10 matching that color (e.g. Red = ×100), or by ×0.1 for Gold or ×0.01 for Silver when the resistance is very small — this is what turns "10" into, say, 10 kΩ or 1 Ω depending on the color chosen.
The 4th band gives the manufacturer's guaranteed accuracy — e.g. a Gold band means ±5%. The Minimum and Maximum values show the real-world range the resistor's actual resistance should fall within, given that tolerance.