I can tell you that it’s supposed to mean “Non Fungible Token”.

I can also define “fungible” for you:

adjective

LAW

(of goods contracted for without an individual specimen being specified) able to replace or be replaced by another identical item; mutually interchangeable."it is by no means the world's only fungible commodity"
What this supposedly means is that “it cannot be duplicated”. Which implies that it’s persistent, because otherwise, if you took over someone’s domain name, you could put something else at that URL.

In which case: it was fungible, now, wasn’t it?

This is why most people who understand computers and the Internet believe that NFT’s are scams, and those selling them are actually selling snake oil.

The only way this would not be true is if something, once placed on the Internet, were permanent, and impossible to change after the fact.

And we know that’s just not true.

Always check and research what you will be investing your money in. It is certainly not easy to find something like this nowadays, but the project https://wakweli.com/ is developing, and thanks to its live integration with NFT platforms it is possible to confirm the authenticity of any tokenized asset, which makes it possible to distinguish genuine assets from fake ones, which is what gives this project a lot of value and it has already been heavily invested in.