Joseph Robinette Biden Jr. (born November 20, 1942) is an American politician who served as the 46th president of the United States from 2021 to 2025. A member of the Democratic Party, he served as the 47th vice president from 2009 to 2017 under President Barack Obama, and represented Delaware in the U.S. Senate from 1973 to 2009.

Born in Scranton, Pennsylvania, Biden moved with his family to Delaware in 1953. He graduated from the University of Delaware in 1965 and the Syracuse University College of Law in 1968. He was elected to the New Castle County Council in 1970 and the U.S. Senate in 1972. As a senator, Biden drafted and led the effort to pass the Violent Crime Control and Law Enforcement Act and the Violence Against Women Act. He also oversaw six U.S. Supreme Court confirmation hearings, including the contentious hearings for Robert Bork and Clarence Thomas. Biden ran unsuccessfully for the 1988 and 2008 Democratic presidential nominations. In 2008, Obama chose Biden as his running mate, and he was a close counselor to Obama during his two terms as vice president. In the 2020 presidential election, the Democratic Party nominated Biden for president. He selected Kamala Harris as his running mate, and they defeated Republican incumbents Donald Trump and Mike Pence. He became the first president to serve with a female vice president.

As president, Biden signed the American Rescue Plan Act in response to the COVID-19 pandemic and subsequent recession. He signed bipartisan bills on infrastructure and manufacturing. He proposed the Build Back Better Act, which failed in Congress, but aspects of which were incorporated into the Inflation Reduction Act that he signed into law in 2022. Beginning in March 2021, Biden confronted elevated inflation rates, which peaked at 9.1% in June 2022 and declined to 2.9% by the end of his term. Biden appointed Ketanji Brown Jackson to the Supreme Court. He worked with congressional Republicans to resolve the 2023 debt-ceiling crisis by negotiating a deal to raise the debt ceiling. Biden responded to record levels of illegal border crossings with extensive use of humanitarian parole and deportations. In his foreign policy, the U.S. reentered the Paris Agreement. Biden oversaw the complete withdrawal of U.S. troops from Afghanistan that ended the war in Afghanistan, leading to the collapse of the Afghan government and the Taliban seizing control. He responded to the Russian invasion of Ukraine by imposing sanctions on Russia and authorizing civilian and military aid to Ukraine. During the Gaza war, Biden condemned the actions of Hamas as terrorism, strongly supported Israel's military efforts, and sent limited humanitarian aid to the Gaza Strip. A ceasefire proposal he backed was adopted shortly before he left office.

Concerns about Biden's age and health persisted throughout his term. He initially ran for reelection and, after the Democratic primaries, became the party's presumptive nominee in the 2024 presidential election. After his performance in the first presidential debate, renewed scrutiny from across the political spectrum about his cognitive ability led him to withdraw his candidacy. Gallup found that Biden had an average approval rating of 42.2% throughout his presidency. He was replaced as the nominee by Vice President Harris, who lost to Trump in the general election. During his term, historians and political scientists ranked Biden in the second quartile of U.S. presidents, diverging from public assessments of his tenure.