Best explanation of "NFT's" (Non-Fungible Tokens) I've come across to date, from someone using the name "queersamus":
Imagine if you went up to the Mona Lisa and you were like "I'd like to own this," and someone nearby went "Give me 65 million dollars and I'll burn down an unspecified amount of the Amazon rainforest in order to give you this receipt of purchase."
So you paid them and they went "Here's your receipt, thank you for your purchase." Then they went to an unmarked supply closet in the back of the museum and posted a handmade label inside it behind the brooms that said "The Mona Lisa is currently owned by (you)," so if anyone wants to know who owns it, they'd have to find this specific closet in this specific hallway and look behind the correct brooms.
If you asked "Can I take the Mona Lisa home now?" they'd say "Oh god no are you stupid? You only bought the receipt that says you own it; you didn't actually buy the Mona Lisa itself, you can't take the Mona Lisa you idiot! You CAN take this, though!" They give you the replica print in a cardboard tube that's sold in the gift shop.
And the person selling you the receipt has at no point in time ever owned the Mona Lisa.
If this doesn't make any sense, or seem like any logical person would be happy about the exchange, then you've understood NFT's perfectly.