Who is Elon Musk? What to know about the world’s wealthiest man, new Twitter owner

After changing his bio to “Chief Twit” and appearing at Twitter’s San Francisco headquarters, Elon Musk has officially closed his $44 billion purchase of the company. The deal gives Musk one of the world’s most powerful megaphones and access to the data of nearly 400 million users. In the first 24 hours of Musk’s Twitter, users reported changes to the site, including lifted shadow bans and reverses to users previously limited on the site.

Musk is a South Africa-born billionaire entrepreneur who serves as CEO of Tesla, a popular electric vehicle manufacturer, and SpaceX. Musk made an early fortune founding PayPal in 1999. EBay bought the company in 2002 for $1.5 billion, and Musk made $180 million from the deal, Time Magazine reported.

Soon after, Musk founded SpaceX, which partners with NASA on missions. Musk’s admirers herald him as a visionary thrusting the world into the future. His ultimate goal with SpaceX is to make humanity a “multi-planet” species by colonizing Mars, and another of his projects seeks to integrate a computer into the human brain . But outside of his ambitious projects, Musk is almost as known for his polarizing online persona. He is popular on Twitter, where he chimes in on politics, talks business openly and embraces the internet’s meme culture. Some of his tweets have landed him in legal trouble.

Multiple news outlets reported Musk closed the deal late Thursday, firing top executives, including the company’s CEO Parag Agrawal. But on Wednesday, Musk tweeted a video of him carrying a porcelain sink into Twitter’s headquarters.