James Earl Carter Jr. (born October 1, 1924) is an American former politician who served as the 39th president of the United States from 1977 to 1981. A member of the Democratic Party, he previously served as the 76th governor of Georgia from 1971 to 1975 and as a Georgia state senator from 1963 to 1967. Since leaving office, Carter has remained engaged in political and social projects, receiving the Nobel Peace Prize in 2002 for his humanitarian work.

Born and raised in Plains, Georgia, Carter graduated from the United States Naval Academy in 1946 with a Bachelor of Science degree and joined the United States Navy, serving on numerous submarines. After the death of his father in 1953, he left his naval career and returned home to Plains, where he assumed control of his family's peanut-growing business. He inherited comparatively little due to his father's forgiveness of debts and the division of the estate amongst himself and his siblings. Nevertheless, his ambition to expand and grow the family's peanut farm was fulfilled. During this period, Carter was encouraged to oppose racial segregation and support the growing civil rights movement. He became an activist within the Democratic Party. From 1963 to 1967, Carter served in the Georgia State Senate, and in 1970 was elected as governor of Georgia, defeating former Governor Carl Sanders in the Democratic primary. He remained in office until 1975. Despite being a dark-horse candidate who was not well known outside of Georgia, he won the 1976 Democratic presidential nomination. In the 1976 presidential election, Carter ran as an outsider and narrowly defeated incumbent Republican president Gerald Ford.

On his second day in office, Carter pardoned all Vietnam War draft evaders by issuing Proclamation 4483. During his term, two new cabinet-level departmentsthe Department of Energy and the Department of Educationwere established. He created a national energy policy that included conservation, price control, and new technology. Carter pursued the Camp David Accords, the Panama Canal Treaties, and the second round of Strategic Arms Limitation Talks (SALT II). On the economic front he confronted stagflation, a persistent combination of high inflation, high unemployment and slow growth. The end of his presidency was marked by the 19791981 Iran hostage crisis, the 1979 energy crisis, the Three Mile Island nuclear accident, the Nicaraguan Revolution and the Soviet invasion of Afghanistan. In response to the invasion, Carter escalated the Cold War when he ended dtente, imposed a grain embargo against the Soviets, enunciated the Carter Doctrine, and led a 1980 Summer Olympics boycott in Moscow. He is the only president to have served a full term in office and not have appointed a justice to the Supreme Court. In the 1980 Democratic Party presidential primaries, he was notably challenged by Senator Ted Kennedy, but won re-nomination at the 1980 Democratic National Convention. Carter lost the 1980 presidential election in an electoral landslide to Republican nominee Ronald Reagan. Polls of historians and political scientists generally rank Carter as a below-average president. His post-presidential activities have been viewed more favorably than his presidency.

In 1982, Carter established the Carter Center, aimed at promoting and expanding human rights. In 2002, he was awarded the Nobel Peace Prize for his work in co-founding the center. He has traveled extensively to conduct peace negotiations, monitor elections, and advance disease prevention and eradication in developing nations. Carter is considered a key figure in the nonprofit organization Habitat for Humanity. He has written over 30 books, ranging from political memoirs to poetry, while continuing to actively comment on ongoing American and global affairs, including the IsraeliPalestinian conflict. At 97 years old, Carter is both the oldest living and longest-lived president, as well as the one with the longest post-presidency, and his 76-year-long marriage makes him the longest married president. He is also the third-oldest living person to have served as a state leader.

The president of the United States (POTUS) is the head of state and head of government of the United States of America. The president directs the executive branch of the federal government and is the commander-in-chief of the United States Armed Forces.

The power of the presidency has grown substantially since the office's establishment in 1789. While presidential power has ebbed and flowed over time, the presidency has played an increasingly strong role in American political life since the beginning of the 20th century, with a notable expansion during the presidency of Franklin D. Roosevelt. In contemporary times, the president is also looked upon as one of the world's most powerful political figures as the leader of the only remaining global superpower. As the leader of the nation with the largest economy by nominal GDP, the president possesses significant domestic and international hard and soft power.

Article II of the Constitution establishes the executive branch of the federal government and vests the executive power in the president. The power includes the execution and enforcement of federal law and the responsibility to appoint federal executive, diplomatic, regulatory, and judicial officers. Based on constitutional provisions empowering the president to appoint and receive ambassadors and conclude treaties with foreign powers, and on subsequent laws enacted by Congress, the modern presidency has primary responsibility for conducting U.S. foreign policy. The role includes responsibility for directing the world's most expensive military, which has the second largest nuclear arsenal.

The president also plays a leading role in federal legislation and domestic policymaking. As part of the system of checks and balances, Article I, Section 7 of the Constitution gives the president the power to sign or veto federal legislation. Since modern presidents are also typically viewed as the leaders of their political parties, major policymaking is significantly shaped by the outcome of presidential elections, with presidents taking an active role in promoting their policy priorities to members of Congress who are often electorally dependent on the president. In recent decades, presidents have also made increasing use of executive orders, agency regulations, and judicial appointments to shape domestic policy.

The president is elected indirectly through the Electoral College to a four-year term, along with the vice president. Under the Twenty-second Amendment, ratified in 1951, no person who has been elected to two presidential terms may be elected to a third. In addition, nine vice presidents have become president by virtue of a president's intra-term death or resignation. In all, 45 individuals have served 46 presidencies spanning 58 full four-year terms.Joe Biden is the 46th and current president of the United States, having assumed office on January 20, 2021.