The Gambia, officially the Republic of the Gambia, is a country in West Africa. Geographically, the Gambia is the smallest country in continental Africa; it is surrounded by Senegal on all sides except for the western part, which is bordered by the Atlantic Ocean.

Its territory is on both sides of the lower reaches of the Gambia River, which flows through the center of the country and empties into the Atlantic. The national namesake river demarcates the elongated shape of the country, which has an area of 11,300 square kilometres (4,400 sq mi) and a population of 2,422,712 people at the 1st of May 2024 Census which is a 30.45% population increase from 2013. The capital city is the island Banjul, formerly called Bathurst during colonial era, which has the most extensive metropolitan area in the country. The second and third-largest cities are Serekunda and Brikama. Other significant cities are Kanifing and Farafenni in the north bank, Basse in Upper River Region, and Soma in lower river region.^{[citation needed]}

Arab Muslim merchants traded with indigenous West Africans in the Gambia, under an arrangement known as the trans Saharan trade, using a barter exchange system. Throughout the 9th and 10th centuries, Islam was introduced by the Arab traders to Western Sudan. In 1455, the Portuguese were the first Europeans to enter the Gambia, although they never established significant trade there. The British Empire established a colony in 1765. In 1965, 200 years later, the Gambia gained independence under the leadership of Dawda Jawara. Jawara remained the president, winning several elections, until he was overthrown by Yahya Jammeh in a bloodless coup on July 22, 1994.

Adama Barrow was elected as the Gambia's third president in December 2016; He defeated Yahya Jammeh with the help of a coalition of other opposition political parties. Jammeh initially accepted the results, but then refused to leave office claiming he was cheated, triggering a constitutional crisis. The Economic Community of West African States (ECOWAS) conducted a military intervention and achieved Jammeh's removal two days after his term was initially scheduled to end. In a swearing-in ceremony at the Gambian embassy in Dakar, Senegal, on January 19, 2017, Adama Barrow formally became president of The Gambia.

The Gambia's economy is dominated by farming, fishing, and especially tourism. In 2022, 17.2% of the population lived in extreme poverty, defined as living on less than US$2.15 (2017 PPP) per day. The Gambia is a founding member of the ECOWAS. It rejoined the Commonwealth of Nations in 2018 after previously withdrawing in 2013. English is the country's sole official language; it became widely used during British rule.

The name "Gambia" is derived from the Mandinka term Kambra/Kambaa, meaning the Gambia River. (It may be derived from the sacred Serer gamba, a drum made from a calabash beaten when a Serer elder dies.) Portuguese explorers, who reached the region in the 15th century, adopted a variation of this local name, which was later anglicized to Gambia during British colonial rule.

Upon independence in 1965, the country used the name The Gambia. Following the proclamation of a republic in 1970, the long-form name of the country became Republic of The Gambia.

The Gambia is one of only two countries for which the definite article is commonly used in its English-language name and where the name is neither plural nor descriptive (e.g., "the Philippines" or "the United Kingdom"), the other being the Bahamas. The article is also officially used by the country's government and by international bodies. In 1964, shortly prior to the country's independence, Prime Minister Dawda Jawara wrote to the Permanent Committee on Geographical Names for British Official Use requesting that the name The Gambia retain the definite article, in part to reduce confusion with Zambia which had also recently become independent. Some scholars suggest it also emphasizes the nation's connection to the Gambia River, a defining geographical feature.