ELI5: Explain Like I'm 5

Currency detector

Okay kiddo, do you know what money is? It's the paper and coins that we use to buy things like toys or candy.

Now, sometimes bad people make fake money that looks like the real thing, but it's not worth anything. That's where the currency detector comes in.

A currency detector is like a special machine that can look at money and tell if it's real or fake. It does this by using special lights and sensors to check if the money has certain features that real money should have.

If the detector sees that the money is real, it will let the person know by making a noise or showing a green light. But if it sees that the money is fake, it will make a different noise or show a red light, so the person knows not to accept it.

That's why sometimes when you give your parents money, they might check it with a machine before giving you change. It's because they want to make sure the money is real and not fake.