So long as the 0V rail is connected to the Arduino 0V rail, the positive rail can be any dc voltage – more or less that the Arduino, so great for 12V motors. And it is compatible with both 5V and 3V ...

As explained by Arduino to Go, each color band on the resistor corresponds to a number but this can differ depending on the band's placement.It's not complicated, but the sheer number of colors ...

Back in 1996, Bob Pease posed an experiment in an April Fools column. “Take an ordinary NPN transistor, ground the base, pull the emitter up to 12 V with a 1 KΩ resistor and measure the colle… ...