Instant ramen noodles have become like cash among inmates in the US.

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Cash is illegal in prisons. And that means everything from tuna to stamps to cigarettes have their own unique value in a trade and barter market.

But ramen has quickly taken over as the most in demand products the prison system offers.

Watch this video to see how ramen took over prison economies and why it’s the default item for trade among inmates.

The Goods by Vox explains what we buy, why we buy it, and why it matters.

Watch the rest of The Goods videos on YouTube: http://bit.ly/2PvjHCB

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