Obama will give his inaugural address outside the US congress [Gallo/Getty]

The inauguration is the formal ceremony marking the transfer of power between US presidents. 

The only event mandated by the US constitution that has to happen for a new president to assume office is the swearing-in before noon on January 20th.  It takes about a minute. 

All the other trappings - the speech, parade, balls, music, and a luncheon - have appeared over time and become tradition.

The events reflect the personality of the new president. 

This year's inauguration will be four days of official and unofficial festivities in and around Washington starting on Sunday. 

During a time of economic and world crisis, having a four-day party may seem out of touch, but the Obamas want to celebrate their popularity and signal a changing of the guard. 

Btween two and four million people are expected to turn out on January 20, 2009 to see Barack Obama sworn in as the 44th president of the US. 

The record crowd may fill the city of Washington, from the Capitol building all the way down the National Mall to the Lincoln Memorial, a distance of nearly 3km. 

The previous record attendance was 1.2 million who turned out for Lyndon Johnson's inauguration in 1965.

240,000 tickets are being given out for the swearing-in ceremony, 5,000 tickets are being sold for seats along the parade route, and everyone else will have to stand along the National Mall (a big grassy area where many federal memorials are). 

Washington will be packed with ordinary Americans who have travelled from across the country, Hollywood celebrities, historic civil rights figures, and foreign dignitaries. 

Obama's overwhelming popularity and a deep desire to forget about the economic crisis and, for some, the last years of the Bush administration, has made the event even more significant. 

History and funding

The inauguration used to be held in the spring on the last day of the Congressional session. 

The first US president, George Washington, was inaugurated on April 30, 1789 in New York City. 

But since the election takes place in November, it was thought there was too much time between the election and the inauguration.  The 20th Amendment to the Constitution was enacted in 1937 changing the date to January 20th. 

The swearing-in ceremony is funded by the US government. 

The government is also giving $10 million towards the rest of the non-constitutionally mandated events. 

But most of the money has come from private donors, just like during the campaign.

Obama hoped to raise up to $45m for the event (even more than the $42.3m spent by Bush in 2005). 

The US newspaper Politico analysed the donor list and found many large individual donors including Wall Street executives.
 
The Inaugural Committee bars money from corporations, and Obama has said he will not take cash from lobbyists or unions.  

The money goes to things like giant TVs on the National Mall for the spectators, portable toilets, concerts, and the balls.

Timetable

Tuesday January 20th is the actual Inauguration Day, and it’s packed with events starting around 9am and ending after 2am.

9:00am:  Church service.

Coffee at the White House with George Bush, the outgoing president.

Procession to the capitol with Bush. 

11:35am: Invocation from controversial evangelical pastor Dr Rick Warren.
 
11:46am: Joe Biden's swearing as vice-president, by John Paul Stevens, a supreme court judge.

11:56am: President's swearing-in by John Roberts, Chief Justice of the US supreme court.

The oath of office, as laid out in the US constitution:  "I (Barack Hussein Obama) do solemnly swear that I will faithfully execute the office of President of the United States, and will to the best of my ability, preserve, protect, and defend the Constitution of the United States." 

They usually add "so help me God" at the end as George Washington did.

The swearing in ceremony has taken place in a number of locations throughout US history, including New York City, the White House, different parts of the US Capitol building, and even at an air field in Dallas. 

This year, as it has for the past several inaugurations, the swearing in ceremony will take place on the west front steps of the US congress. 

Obama will be surrounded on the platform by his family, the Bushes, past and future Cabinet members, the justices of the Supreme Court, and dignitaries. 

12:01pm: Inaugural address by Obama, now president of the US. 

Obama is known for his soaring speeches [Reuters]

Politico reports that he wants a tone that is "soaring but accessible, simple but inspiring, urgent and confident all at once".

He is expected to inspire, uplift, and energise.  Obama is a gifted speechwriter and deliverer, so if he does anything less than make the best speech of his life, there will be a lot of disappointment. 

He may signal a new direction on any number of fronts – foreign policy, public service, bipartisanship, public policy, etc.  But he will certainly be short on specifics.

12:32pm: Departure of former president and Dick Cheney, the former vice-president:  In past years, the new president and vice-president have escorted their former counterparts out through a military cordon.

12:52pm: Signing ceremony, where Obama will make his first official executive acts.  He will sign executive orders possibly fulfilling campaign promises.

Some possibilities are:  Lifting the ban on stem cell research, closing the Guantanamo Bay prison camp, banning harsh interrogation of al-Qaeda suspects, or allowing abortion services at overseas family planning centres funded by the US government.

1:05pm: Inaugural luncheon -  this is one of the few times when the top tier of the US Government is in one room. 

The president, vice-president, supreme court, cabinet nominees, and members of the congressional leadership will all attend. 

Obama will also address members of congress and probably ask them to sign the $850bn stimulus package.  

Approximately 200 guests will attend the luncheon. 

The Obamas and Bidens then review troops present at the event.

2:36pm: Trip between the US congress and the White House.

Newly sworn-in presidents and their families traditionally drive and walk the 2.7km along Pennsylvania Avenue between congress and the White House. 

Preparations for the event have been under way for months [GALLO/GETTY]

Then the president and family will stop in front of the White House and watch the parade go by from an enclosed, heated reviewing stand.

Inaugural parade – this lasts about two hours.

This year's parade will include 90 music, cultural, and community groups. About 5,000 tickets were sold to the general public for seats along the parade route. 

After the parade ends, hopefully before dark, the Obamas have a bit of time to get ready for the inaugural balls. 

There are dozens of inaugural balls on or around January 20th where participants can dance the night away. 

There are 10 official balls that the Obamas will attend, including ones sponsored by Obama's home states of Hawaii and Illinois.

There's also a Neighborhood Inaugural Ball that will be broadcast on the internet, and a Youth Ball for people aged 18-35. 

These are set to go on until late.

Wednesday January 21:

The Obamas and Bidens have invited dignitaries to attend a prayer service at the Washington National Cathedral on Wednesday morning. 

It is the last inaugural event.

Then the business of governing can begin.