On Monday morning, U.S. President Barack Obama was publicly sworn in during a ceremony in front of the U.S. Capitol, to herald the start of his second term.
After the swearing-in, Obama delivered his Inaugural Address, which will be followed by numerous festivities, including the Inauguration Parade. (Here is a complete list of today's events.)
Today's oaths are ceremonial - President Obama and Vice President Joe Biden took their official oaths of office for their second terms in two, separate private ceremonies on Sunday.
The inauguration ceremonies and related events Monday will be open to members of the public, with about 800,000 anticipated in the country's capital for the festivities.
Chief Justice John Roberts administered the oath of office to Obama in the Blue Room of the White House, with the aid of a Bible that belonged to First Lady Michelle Obama’s paternal grandparents.
Supreme Court Justice Sonya Sotomayor administered the oath of office to Biden at the vice president's U.S. Naval Observatory Residence in Washington, with the assistance of the Biden family Bible.
Both the president and the vice president began their Sunday by participating in a wreath-laying ceremony at the Tomb of the Unknowns at the Arlington National Cemetery in Virginia.
And the nation's leaders for the next four years ended it by attending an inaugural reception at the National Building Museum in Washington.
Below are a few of the many images captured of the country's first and second families during the inaugural events.