SpaceX, Elon Musk’s rocket and artificial intelligence company, finished its record-setting first day of trading on the stock market having made Musk the world’... (opens in new tab)

SpaceX, Elon Musk’s rocket and artificial intelligence company, finished its record-setting first day of trading on the stock market having made Musk the world’s first trillionaire, ushering in a new era of ultra-affluence and widening wealth inequality. Here’s what to know: