Elon Musk's $44 billion deal to buy Twitter will make the world's richest person the master of a global platform where he has grabbed the spotlight with musings, quips, and barbs.

Here is a look back at some attention-grabbing Musk moments on Twitter, where he is followed by more than 85 million people.

In the week leading up to his unsolicited campaign to take the one-to-many messaging service private, Musk fired off tweets joking about removing the "w" from Twitter's name and turning its San Francisco offices into housing for the homeless since "no one shows up."

He also conducted a Twitter poll asking whether there should be a button for editing tweets already posted -- a change that many tweeters have long demanded.

Musk has used Twitter as a stage to ask whether the social media network was "dying" and to call out users such as singer Justin Bieber, who are highly followed but rarely post.

He quipped during an on-stage interview at a recent TED conference in Vancouver that his tweets are "stream of consciousness," often authored while on the toilet.

Musk made his official Twitter debut on June 4, 2010, evidently to thwart others from tweeting in his name.

"Please ignore prior tweets, as that was someone pretending to be me," he wrote. "This is actually me."

Musk follows just 114 people, according to his profile.

Many of his tweets have been about Tesla and his private space exploration enterprise SpaceX, with some devoted to topics such as politics, cryptocurrency and the environment.

In July of 2018, Musk used Twitter to insult British caver Vernon Unsworth, who was part of a dramatic effort to rescue boys trapped in a flooded cave in Thailand.

Musk had sent a self-designed submarine that Unsworth had mocked as a publicity stunt not useful in the effort.

Musk's tweet, which included the unsubstantiated accusation calling the diver a "pedo guy" was deleted, but Unsworth filed a defamation lawsuit that ended with a jury ruling in favor of Musk in Los Angeles at the end of 2019.

Elon Musk made his official Twitter debut on June 4, 2010, evidently to thwart others from tweeting in his name -- "This is actually me," he wrote
Elon Musk made his official Twitter debut on June 4, 2010, evidently to thwart others from tweeting in his name -- "This is actually me," he wrote AFP / JIM WATSON

Musk found himself in the crosshairs of regulators at the US Securities and Exchange Commission (SEC) in August 2018 after he tweeted he might take Tesla private.

"Am considering taking Tesla private at $420," Musk said in the tweet, which some took to include a playful reference to "4-20" jargon used to refer to cannabis.

"Funding secured."

The market reacted to Musk's surprise comment, which he never followed through on or provided proof to support.

A settlement with US regulators, who accused Musk of misleading investors, resulted in him stepping down as chairman of the Tesla board and paying a $20 million fine.

Musk was also required to have tweets directly related to Tesla's business be pre-approved by legal counsel at the car maker.

His clashes with US regulators include him tweeting that SEC actually stands for "Shortseller Enrichment Commission," inferring they were on the side of those betting against Tesla.

Offbeat products Musk has sold include red "short shorts" to mark Tesla shares climbing to the chagrin of those who tried to make money from the stock going down.

In November of 2021, Musk used Twitter to poll his followers regarding whether to sell 10 percent of his Tesla shares. The query came thanks to a controversy over whether unrealized gains are a way to dodge taxes.

He vowed to abide by the outcome of the vote, which was in favor of selling the shares.

The SEC is investigating whether Musk told his brother, Kimbal, about the plan ahead of time to allow him to make favorable moves with Tesla shares, according to the Wall Street Journal.

Musk challenged Russian President Vladimir Putin to "single combat" in a tweet fired off on March 14, 2022.

He said the winner would get Ukraine, which Russia invaded weeks earlier.

Musk recently posted the results of a poll asking whether his Twitter followers think the platform "rigorously adheres" to the principle that free speech is essential to a functioning democracy.

The more than two million votes resulted in the majority saying "no."

When his purchase of Twitter was announced, Musk tweeted "I hope that even my worst critics remain on Twitter, because that is what free speech means."