But due to an arcane system in the US, presidents stay in office for more than two months after their replacement is chosen.

So what happens in the strange twilight zone between one president and another? A strange mix of customs, courtesies and the shoring-up of one’s legacy:

Presidents will usually meet with their successor in the days after the election, and on the morning of the inauguration.

Because presidents are usually, though not always, replaced by someone of the other party, these meetings are often tense or awkward.

The meeting between Barack Obama and Donald Trump in 2016 was famously cold.

In 2020, Donald Trump did not invite Joe Biden to the White House at all.

But they can also be cordial.

George W Bush’s twins Jenna and Barbara gave a special tour to Obama’s young daughters Sasha and Malia in 2009.

And George HW Bush’s handwritten letter to Bill Clinton, who defeated him in 1992, is an act of remarkable grace.

“There will be very tough times, made even more difficult by criticism you may not think is fair,” Bush wrote.

“Don’t let the critics discourage you or push you off course.”

But presidential staffers are not always as magnanimous as their bosses.

When the younger Bush’s team arrived in the West Wing in 2001, many found the W missing from their computer keyboards.

In other instances of vandalism, glue was smeared on desk drawers and doorknobs were taken.

Joe Biden may be fading from the public consciousness, but he is still keeping an active schedule.

Since the election Biden has made official trips to Brazil, Peru, Cape Verde and Angola.

And a final visit to Italy and Vatican City was cancelled so he could oversee the federal response to the California bushfires.

But his active schedule has not impressed Americans.

While presidents normally see their approval ratings go up when they’re leaving office, Biden remains deeply unpopular.

Not only does the president stay in office for months after the election, but all other elected officials in Washington do too.

And Congress can and does pass legislation with majorities that technically lost office weeks earlier.

It’s rare for major legislation to be passed in what’s called a “lame duck” session.

But often the sessions are used to confirm judges to the bench or to pass continuing resolutions to keep the government funded.

The mammoth task that comes with a new administration is filling all the positions in the bureaucracy.

There are 11,000 appointments to be made by the incoming administration.

Incoming White House chief-of-staff Susie Wiles told the New York Times she aspired to fill 2000 of those positions by January 20.

By contrast, only 25 positions had been filled when Trump took office for the first time in 2017, leading to widespread chaos in Washington.

It is also in the final weeks of an administration that presidents carry out acts that would have been too unpopular to do before an election.

Trump pardoned several key advisors in his last weeks in office.

And Clinton controversially pardoned his younger brother for crimes committed in the 1980s.