After eight years in the White House Barack Obama will give his final speech as American president today.
The 55-year old will return to his hometown of Chicago where he delivered his victory speech in 2008, when he became America's 44th President and made history as the country's first black president.
Tickets for the farewell event, which is free, ran out in 30 minutes at the weekend after some 7000 people braved freezing conditions to wait in line outside the McCormick Place convention centre where the speech will take place.
It is the first time a president has returned to his hometown to deliver such a speech.
The speech continues a tradition set in 1796 when George Washington addressed the American people for the last time as president.
Mr Obama described the event as "a chance to say thank you for this amazing journey", to celebrate the ways the country had changed and "to offer some thoughts on where we all go from here".
Barack Obama swept into office on a tide of hope and optimism, but his eight years in office have been marked by frustration and disappointment.
Faced with a fierce Republican majority in Congress, Mr Obama struggled to advance much of his political agenda, garnering the label as a lame duck President.
His signature Affordable Care Act - known as Obamacare - faced staunch political and electoral opposition and ended up a watered-down piece of legislation that became difficult to implement. Despite the challenges, more Americans now have health insurance than they did in 2011 and more than 8.8 million Americans have signed up for coverage. However, Donald Trump has vowed to repeal Obamacare as one of his first acts of office.
Gun violence and mass shootings marked Mr Obama's presidency. In an emotional speech after the 2012 Sandy Hook school shootings, the President promised tough new gun control legislation. He ran head on into the National Rifle Association's lobbying power and failed to get it passed. He said America's failure to pass commonsense gun safety controls is the biggest frustration of his presidency.
On foreign policy Mr Obama leaves the White House with two prominent feathers in his cap - the Iran nuclear deal and normalised relations with Cuba.
He oversaw the drawdown of US forces in Iraq and Afghanistan - fulfilling a key campaign promise - and was in the White House when elite US troops killed al-Qaeda leader Osama bin Laden in Pakistan.
He promised to reset US-Russian relations, but those plans were derailed by Russia's Ukrainian intervention and its backing of Syrian President Bashar al-Assad in the Syrian conflict.
In terms of the environment, the Obama administration helped negotiate the Paris climate agreement and enacted a host of new regulations governing pollution from coal-fired power plants and limiting coal mining and oil and gas drilling both on federal lands and in coastal waters.
Mr Obama used his executive authority to designate 548 million acres of territory as protected habitat - more than any other president.
On trade, President Obama completed two major trade agreements - the Trans-Pacific Partnership and the Transatlantic Trade and Investment Partnership - the cornerstone of his second term in office. However the TPP is destined for the rubbish bin with a new Trump presidency.
Economically Barack Obama has overseen a turnaround. When he took office he inherited a flat economy struggling with the Global Financial Crisis. He passed an economic stimulus package, and later additional stimulus in the form of tax cuts. He bailed out the US auto industry and funded public works projects. Mr Obama leaves behind a growing economy. He is credited with creating more than 17 million jobs since he took office, with unemployment running at a low five percent.
However, a major mark against him is the increase in national debt as he used deficit spending to stimulate the economy.
Perhaps the biggest blot on his legacy copybook is the crumbling of his own Democratic Party's political power.
In 2009, when Mr Obama swept to power, Democrats had large majorities in the US Congress and control of 29 of 50 governorships. Since then, he has seen his party's power steadily erode. The House of Representatives has been in Republican hands since 2010, the Senate since 2014. Democrats control the governor's mansion in only 16 states.
The situation is more dire in state legislatures - the proving grounds for young politicians with national ambitions. Republicans hold sway in 32 legislatures, while Democrats have majorities in only 12. The rest are divided.
Mr Obama's legacy is in doubt as his successor Donald Trump has promised to undo much of his agenda.
Ultimately it will be up to history to judge his presidency.
Unusually for an outgoing president, Barack Obama will stay in Washington D.C.
The Obamas will move into a brownstone house in the upmarket suburb of Kalorama where they will stay until the youngest daughter Sasha finishes high school.
Mr Obama has hinted that he will spend more time working with My Brother's Keeper Alliance, an initiative which improves the lives of poor black and Latino boys.
Speaking last year, Mr Obama said that the Alliance "will remain a mission for me and for Michelle not just for the rest of my presidency, but for the rest of my life".
He is likely to write a book on his life in the White House.
His previous memoirs - Dreams From My Father and The Audacity of Hope - were both international bestsellers.
In 2014 Mr Obama told Reuters - "I know what I'll do right after the next president's inaugurated. I'll be on a beach somewhere, drinking out of a coconut."
Mr Obama's term officially ends at midday on the 20 January in Washington as Donald Trump is inaugurated as America's 45th president.