This week, Visa announced that it purchased a Crypto Punk NFT (non-fungible token) for $ 150,000.00 on the Ethereum blockchain. This first statement can raise many questions for you: What is an NFT? Blockchain? Ethereum? This column will aim to give you an overview of these revolutionary concepts. Blockchain is a database that collects information in blocks. Think of something like a cell in Excel that can contain a number. Each block has a certain storage capacity, which once filled in with information, is chained to another previously generated block. The set of chained blocks is called blockchain (chain of blocks). Three advantages of the blockchain are its: i) immutability, a block cannot be modified without leaving a trace, any change is permanently established; ii) traceability, the chaining of blocks traces an irreversible time line, where each transaction can be verified in time; and iii) decentralization, the technology is not managed by a central system (government, corporation), but by a decentralized computer system. Ethereum is a blockchain system that allows applications to be deployed on its network called smart contracts. Ether is the cryptocurrency used to carry out transactions on its platform; In other words, if I want to participate in a smart contract, I must use Ether as a currency. An NFT is a unit of data set in the blockchain that certifies that a digital asset is unique and not interchangeable. A meme does not have an owner, an NFT does. An NFT can be a photo, audio, video, and other digital files. What distinguishes an NFT from other digital files? The non-fungibility of an NFT distinguishes it from other digital products. That is, there is only one single file for that NFT. An apple is fungible because it can be exchanged for another apple, it is an exchangeable good. Instead, there is only a Mona Lisa by Da Vinci or a Guernica by Picasso, they are not interchangeable. The same happens with an NFT, there is only one in the entire network. When you acquire an NFT, the blockchain records the transaction, with this record it is established who is the owner of that asset. The ownership of that NFT is permanently registered on the blockchain until they decide to sell it later. On the other hand, if I bought the Mona Lisa, I would probably do so on a traditional contract. That written document certifies me as its rightful owner. What happens if someone disputes my legitimate ownership of the Mona Lisa with another contract? We would have to go to court to fight. On the other hand, if this happens with an NFT, it is enough to review the blockchain registry to determine who is the rightful owner. This dramatically reduces transaction costs, offers certainty and transparency. A contract can be forged, a blockchain record cannot be modified. Visa purchased a Crypto Punk NFT using the Ethereum blockchain. This NFT is not a Mona Lisa, it is a pixelated image of a man with a mohawk. When you Google this NFT you will be surprised, it will say that this drawing could have been made by a child in Paint. The interesting thing is to see how a serious company participates in transactions with these nascent technologies. Today is a simple picture, tomorrow it can be houses, trusts, loans and more. Welcome to the world of crypto, blockchains, smart contracts and NFTs. * The author is a lawyer and a teacher in administration and public policy.