A non-fungible token (NFT) is a unique digital identifier that is recorded on a blockchain and is used to certify ownership and authenticity. It cannot be copied, substituted, or subdivided. The ownership of an NFT is recorded in the blockchain and can be transferred by the owner, allowing NFTs to be sold and traded. Initially pitched as a new class of investment asset, by September 2023, one report claimed that over 95% of NFT collections had zero monetary value.
George M. Church sold NFTs of an "artistic representation" of his genome and likeness in 2022.
A blockchain is a distributed ledger with growing lists of records (blocks) that are securely linked together via cryptographic hashes. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data. Since each block contains information about the previous block, they effectively form a chain, with each additional block linking to the ones before it. Consequently, blockchain transactions are irreversible in that, once they are recorded, the data in any given block cannot be altered retroactively without altering all subsequent blocks.
Bitcoin, Ethereum and Litecoin transactions per day (January 2011 – January 2021)
Blockchain panel discussion at the first IEEE Computer Society TechIgnite conference