Twitter boss Jack Dorsey has sold his first tweet as an NFT for just over $2.9 million dollars on Monday. The tweet is in the form of a non-fungible token (NFT) – a kind of unique digital asset that has exploded in popularity so far in 2021. Each NFT has its own blockchain-based digital signature, which serves as a public ledger, allowing anyone to verify the asset’s authenticity and ownership. The tweet – “just setting up my twttr” – was Dorsey’s first tweet, made on March 21, 2006.