Jack Dorsey posted it on March 21, 2006, back when the service was still called 'twttr' and had no vowels in its name. In 2021, Dorsey auctioned the tweet itself as an NFT, and it sold for a reported $2.9 million to a Malaysia-based buyer. When that buyer tried to resell it about a year later, the highest bid came in at only a few thousand dollars.