Resistor Color Code
 

FIRST AND SECOND COLOR BAND

Black 0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Gray 8
White 9
 

THIRD COLOR BAND

Black x1
Brown x10
Red x100
Orange x1k
Yellow x10k
Green x100k
Blue x1 Meg
Silver div 100
Gold div 10
 

FOURTH COLOR BAND (tolerance)

Gold 5%
Silver 10%
None 20%
 

Barrel-Type Connector Convention

TIP POSITIVE
- ----------(o----------- +

TIP NEGATIVE
+ ----------(o---------- -