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Hello, this is 6 Minute English from BBC Learning English. I'm Neil.

And I'm Sam.

People collect all kinds of things for a hobby, from stamps and coins to comics and football stickers.

Do you collect anything, Sam?

I used to have a big collection of Pokemon cards, but I have no idea where they are now.

Well, maybe you should start looking for them because all kinds of collectibles,

that's objects that people want to collect, are selling for big money on the internet.

It's all part of a new tech craze called non-fundable tokens or NFTs for short.

Non-fundable tokens?

Basically, NFTs are unique one of a kind items that can be bought and sold like any physical object,

but only exist in the digital world.

Tokens can be thought of as certificates of ownership for these virtual possessions.

Hmm, okay. I understand the token part, but what does non-fundable mean?

If something is fungible, it can be interchanged, like money, for example.

With money, you can swap a £10 note for two £5 notes and it will have the same value.

Ah, so something non-fundable cannot be interchanged with something else.

Is that because it has special features that make it unique?

Exactly. Imagine something totally unique like the Mona Lisa.

You can take a photo of the painting or buy a copy of it,

but there will only ever be the one original painting.

Ah, I can see that the Mona Lisa is one of a kind and extremely valuable,

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