On March 21, 2006, Jack Dorsey posted a simple message: “just setting up my twittr”.

That was, of course, the very first post on the site that is still best known as Twitter, even after being renamed X by its new owner Elon Musk (the deal is still being fought over in court). X then became part of Musk’s xAI, which itself has become part of SpaceX.

Musk cut the company’s workforce dramatically and spurred new controversies by incorporating xAI’s chatbot Grok, which dubbed itself “MechaHitler” and was used to create widespread sexual deepfakes, including of real women and children.

While X retains a strong hold on some user groups, including swaths of the tech industry, it also faces competition from services like Bluesky and Meta’s Threads. One report suggests that Threads recently overtook X in daily mobile users. (All of these primarily text-based services are dwarfed by apps like Instagram and TikTok.)

As for Dorsey’s original tweet, the Twitter co-founder later sold it as an NFT for $2.9 million. But its value has reportedly plummeted, with the buyer unable to resell it.