An NFT is a verifiable digital asset vouchsafed by blockchain technology. NFTs are not exchangeable like currencies — as each is unique and can’t be replicated.

NFTs use blockchain, the technology ledger backing cryptocurrencies like bitcoin  BTCUSD, -0.25%   and ethereum ETHUSD, +0.27%,  which are databases of linked information to record ownership or transactions of a product. While NFTs use blockchain, they are not currencies and should be treated more like rare trading cards than money.

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The winner of the auction for Dorsey’s tweet is receiving “a digital certificate of the tweet, unique because it has been signed and verified by the creator.”

The auction winner will also get the metadata of the original tweet including “when the tweet was posted, what the text contents are of the tweet, the timestamp of the tweet, and the digital signature from the creator’s crypto wallet address.”

The auction winner, Twitter user @sinaEstavi, thanked Dorsey in a tweet shortly after the bidding ended.

The user did not respond to a request for comment.

Dorsey had previously stated that the proceeds from the auction would be converted to bitcoin and donated to COVID-19 relief in Africa.

NFTs have exploded in popularity of late. In the past few months people have spent hundreds of millions of dollars on digital assets like NBA Top Shot moments and digital art. One piece of digital art by the artist known as Beeple sold for $70 million.