Barack Hussein Obama II (i /bəˈrɑːk huːˈseɪn oʊˈbɑːmə/ bə-RAHK hoo-SAYN oh-BAH-mə; born August 4, 1961) is the 44th and current President of the United States. He is the first African American to hold the office. Obama previously served as the junior United States Senator from Illinois, from January 2005 until he resigned after his election to the presidency in November 2008.

Originally from Hawaii, Obama is a graduate of Columbia University and Harvard Law School, where he was the president of the Harvard Law Review. He was a community organizer in Chicago before earning his law degree. He worked as a civil rights attorney in Chicago and taught constitutional law at the University of Chicago Law School from 1992 to 2004.

Obama served three terms in the Illinois Senate from 1997 to 2004. Following an unsuccessful bid for a seat in the U.S. House of Representatives in 2000, he ran for United States Senate in 2004. Several events brought him to national attention during the campaign, including his victory in the March 2004 Democratic primary and his prime-time televised keynote address at the Democratic National Convention in July 2004. He won election to the U.S. Senate in November 2004. His presidential campaign began in February 2007, and after a close campaign in the 2008 Democratic Party presidential primaries against Hillary Rodham Clinton, he won his party's nomination. In the 2008 general election, he defeated Republican nominee John McCain and was inaugurated as president on January 20, 2009.

As president, Obama signed economic stimulus legislation in the form of the American Recovery and Reinvestment Act in February 2009. The U.S. economy has grown for the past two successive fiscal quarters after several quarters of a severe economic recession, although unemployment remains high. On October 8, 2009, Obama was named the 2009 Nobel Peace Prize laureate. In March 2010, Obama signed the Patient Protection and Affordable Care Act into law, the first comprehensive health care reform legislation in decades.