An NFT (Non-Fungible Token) is a data structure that points at a particular data object in a unique way. See it as a way of naming digital objects, such as photos, texts, audio or video, in a way that allows referring to them with no ambiguity.

The ability to refer to data objects allows to “mention” them in transactions. This seemingly trivial ability, when combined with the ability to create immutable records of transactions (as provided by Blockchains), allows us to create immutable records that refer to data objects.

Technically, NFTs do not require blockchains. You could take a photo of a cat, create an NFT for this photo, which is essentially a unique pointer to (or: a descriptor of) it, and then go on to write a real contract on paper that says “this photo of a cat, bearing this unique ID, is hereby assigned to John Smith”, whatever this assignment means.

Blockchains and smart contract technologies allow for such digital agreements to be stored in a public immutable record that does not allow anyone to change it once it was written. The combination of NFTs and blockchain-based smart contracts thus allows us to securely record agreements that declare ownership of digital goods. If you have any file (photo, text, video, etc.), you can create an attestation that tells the entire world that you assign this file to be owned by whoever. What does this “ownership” mean? – Good question; but whatever it means, billions of dollars have already been paid towards such ownerships. Is this real? The money surely is, but is also the value?