What number President was Barack Obama of the United States?

Barack Obama served as the 44th President of the United States. He was in office from January 20, 2009, to January 20, 2017. This aligns with historical records that mark his presidency as a significant period in American history, focusing on issues such as healthcare reform, economic recovery following the Great Recession, and foreign policy changes. The sequence of U.S. presidents is numbered in a linear fashion, so understanding that Obama is 44 reflects the continuity of the office and acknowledges the previous presidents before him. This context solidifies why the choice indicating him as the 44th is accurate and reflects his place in the historical timeline of American leadership.