Presidential inaugurations have their basis in the US Constitution and are normally celebratory but very organised events.
But on a few occasions, the celebrations, pressure or just the weather have conspired against the best-laid plans.
Here are some of the more memorable moments from past inaugurations:
2009: The President who almost wasn't a President
Barack Obama took was sworn in for the first time on 20 January 2009 in front of a crowd of about 1.8 million people.
There was an awkward moment when Chief Justice John Roberts misplaced a word in the constitutionally required oath. Instead of saying, "that I will faithfully execute the office of president of the United States," Roberts rearranged the words and said "faithfully" after "president of the United States".
Obama started to respond, but abruptly stopped to let Roberts correct the mistake. Roberts started speaking again and put "faithfully" in the right place but left out the word "execute." Obama then repeated Roberts' original, incorrect version.
The White House maintained that Obama was president regardless of the oath fumble. Even so, Roberts administered the oath again a day later, perfectly, before a small group of reporters in the White House Map Room.
1993: The President who did Rock 'n' Roll
On the evening of his first inauguration, Bill Clinton delighted thousands at a packed room at a ball in Arkansas when he played 'Your Momma Don't Dance and Your Daddy Don't Rock 'n' Roll' on his trademark saxophone with Ben E. King.
Clinton would take up the sax again and jam with Clarence Clemons, and at another ball with Herbie Hancock and Thelonious Monk Jr.
1985: Snow stops play
At Ronald Reagan's second inauguration, Arctic conditions meant that the ceremony had to be moved indoors to the Capitol Rotunda. He delivered his inaugural address to a crowd of invited guests.
It also meant that Reagan was the only American president since 1805 to not parade down Pennsylvania Avenue to the White House.
1981: A double celebration
Ronald Reagan was inaugurated for the first time on an unusually warm January day. But just minutes after being sworn in, news arrived that Iran had freed 52 American hostages it had held for 444 days.
A complicated deal worked out in the final weeks of his predecessor's administration came good just in time for President Reagan to take the glory.
He was able to announce to congressional leaders the good news that planes bearing prisoners had left Iranian airspace and "they are now free of Iran".
1977: The president who walked the line
Jimmy Carter shunned the customary limousine ride from the Capitol down Pennsylvania Avenue opting instead to walk the mile-plus parade route.
He initially strolled hand in hand with his wife, Rosalynn, but was eventually joined by his three sons Jack, Chip and Jeff.
Later, near the end of the parade route, he was joined by his youngest child, nine-year-old Amy, who took her place between her parents, all three holding hands.