ELI5: Explain Like I'm 5

Take a penny, leave a penny

Okay, so you know how when you go to the store and you’re buying something and it costs a certain amount of money? And you might have some coins in your pocket, like pennies, but you don’t have enough to pay for the whole thing?

Well, sometimes the store has a little dish or container near the cash register that says “Take a penny, leave a penny.” What that means is, if you need some extra pennies to pay for your thing, you can take one or two from that dish to help you out. But then, if you have extra pennies when you’re done paying, you can put them back in the dish so that someone else can use them next time.

It’s like sharing with other people who might need your help, and they can share with you too. And it helps keep the store running smoothly, because everyone can pay for what they need without any problems.
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