Elon Musk. Jeff Bezos. Mark Zuckerberg. Sundar Pichai. They are all here for Donald Trump's inauguration as he makes a remarkable return to the presidency.
At 78, Mr Trump is only the second president since the founding of the republic to win the White House after being defeated for re-election.
The swearing-in ceremony in Washington, moved indoors due to glacial temperatures, is being attended by former presidents, foreign dignitaries, tech and business executives, and an assortment of performers and celebrities.
Four years ago, Mr Trump skipped president Biden's inauguration, arguing that the election had been stolen from him.
Cut to present, Joe Biden and his successor Donald Trump left the White House together on Monday for the Capitol building, where the Republican president-elect was to take the oath of office.
Donald Trump has vowed to unleash a blitz of executive orders undoing outgoing president Joe Biden's legacy, and to launch immediate deportations of undocumented migrants.
The 47th US president said he would "stop the invasion of our borders" and reverse "woke" policies including "transgender insanity" in US schools.
Mr Trump -- who said during the election campaign he would only be a dictator on "day one" -- has promised to sign around 100 executive orders within hours of taking office.
They include declaring a national emergency on the southern US border with Mexico, and undoing Biden's directives on diversity and oil drilling.
Mr Trump added that supporters would be "very happy" with a decision pardoning January 6 rioters.
For the rest of the world, Trump's return means expecting the unexpected.
