"Hello, Twitter! It's Barack. Really! Six years in, they're finally giving me my own account." With that inaugural tweet sent from a smartphone in the Oval Office before jumping on Marine One on Monday, the President of the United States Barack Obama - or @POTUS - cast off security and bureaucratic chains in place since he was elected, AFP reported.
The account - which already had nearly 150,000 followers in the first half hour and a million followers shortly after - will also allow Mr Obama to tweet directly for the first time.
Until now, Mr Obama has tweeted through his executive staff @WhiteHouse or the remnants of his campaign staff @BarackObama.
"The @POTUS Twitter account will serve as a new way for President Obama to engage directly with the American people, with tweets coming exclusively from him," the White House said.
Here are five other world leaders who tweet personally.
1) Estonian President Toomas Hendrik Ilves
The Estonian President joined Twitter in mid-May 2012 and became an instant hit for his frank tweets and outspokenness, a study by public relations agency Burson-Marsteller called Twiplomacy, found.
Ilves, 61, sees his mission on Twitter as combating ignorance and inaccuracy when it comes to his country.
2) European Council president Donald Tusk
Former Polish Premier Donald Tusk renamed his personal Twitter account @DonaldTusk - from @PremierTusk - once he was elected president of the European Council. Tusk created his personal account on Sept 17 2011 and tweets about two or three times per month, depending on the political agenda.
Two thirds of his tweets are replies, and he often interacts with prominent Polish politicians and journalists. He tweets mostly in Polish and sometimes tweets about his private life. On May 26, 2014, he tweeted a black-and-white photo of his mother.
3) Norway Prime Minister Erna Solberg
Norway's Prime Minister was found to be the second-most conversational world leader on Twitter in the study by Burson-Marsteller.
She writes and tweets herself despite suffering from dyslexia and making the occasional spelling mistake. She became Norway's second female Prime Minister in September 2013, but had a social media account before that.
She has been on Twitter since Sept 24 2008, and tweets mainly in Norwegian. She tweets about official matters and personal matters, and is open about her dyslexia.
Her most popular tweet was one in June 2013 to her political opponent, former Prime Minister Jens Stoltenberg: "OK @JensStolentberg I am ready for the challenge #2election".
4) Ecuador President Rafael Correa
The Ecuador president's Twitter style can be seen as contentious. He takes to tweets to give his personal opinions on many issues, including media analysis of his leadership.
He is the third most conversational world leader with 81 per cent of his tweets being replies to his followers, usually asking his different ministries to "deal with it". Rafael Correa only follows five other Twitter users.
5) Rwanda President Paul Kagame
Rwanda's President is the most followed African leader on Twitter. He was found to be the most conversational world leader on Twitter with 86 per cent of his tweets being replies to his followers and anyone who wants to discuss African issues with him.
His account was linked to a notorious troll in early 2014. While the @PaulKagame account connects directly with his followers, it does not follow any other Twitter users, not even the 48 world leaders who follow him.
Paul Kagame tweets from his BlackBerry generally in the evenings, and the account is most active on Sundays.
Sources: Twiplomacy, AFP
