A: Hey Woz - whatcha doin?
W: Oh hi Adabot - I was just adding some power protection to this circuit
A: Interesting - why does the circuit need to be protected?
W: Well a circuit needs to be protected for a couple of reasons. One example is if I was to connect a battery to this incorrectly then electrical current might flow in the wrong direction and damage some of the components.
A: Oh - how do you make sure that doesn’t happen?
W: Well, we use a diode!
W: By placing a diode at the circuit’s power input we ensure that current will only flow in one direction - the correct direction that we’ve designed the circuit to work with.
A: So - a diode is like a one way street for electrons?
W: Exactly - the electrons can only flow through the diode in one direction and they have a really hard time going back the other way.
W: The stripe indicates which end of the diode acts like a wall to block the electrons.
A: Diode! Protector of circuits!
W: Yes, but diodes do more than just protect circuits, Adabot.
A: Oh? What else do they do?
W: Some diodes emit light when we pass current through them. We like to call these “light emitting diodes” or L-E-Ds for short. Maybe you’ve heard of them?
A: LEDs? I love LEDs!!
W: I thought so!
A: So that’s what “D” stands for in LED. D is for - Diode!
W: That’s right.
W: Well, looks like this circuit’s all done - how about we go test it out?
W: Adabot - are you coming?
A: Sorry Woz - I’m an electron in a diode - I only go in one direction!
A: Ow … Ow …
W: Oh Adabot, let’s go.