The Columbian exchange, also known as the Columbian interchange, was the widespread transfer of plants, animals, precious metals, commodities, culture, human populations, technology, diseases, and ideas between the New World in the Western Hemisphere, and the Old World (Afro-Eurasia) in the Eastern Hemisphere, in the late 15th and following centuries. It is named after the Italian explorer Christopher Columbus and is related to the European colonization and global trade following his 1492 voyage. Some of the exchanges were purposeful. Some were accidental or unintended. Communicable diseases of Old World origin resulted in an 80 to 95 percent reduction in the number of Indigenous peoples of the Americas from the 15th century onwards, most severely in the Caribbean. The cultures of both hemispheres were significantly impacted by the migration of people, both free and enslaved, from the Old World to the New. European colonists and African slaves replaced Indigenous populations across the Americas, to varying degrees. The number of Africans taken to the New World was far greater than the number of Europeans moving to the New World in the first three centuries after Columbus.

The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas. The term gained prominence in the early 16th century during Europe's Age of Discovery, after Italian explorer Amerigo Vespucci published the Latin-language pamphlet Mundus Novus, presenting his conclusion that these lands, soon called America based on Amerigo's name, constitute a new continent.