Puerto Rico (pronounced /ˌpwɛrto ˈriːko/ or /ˌpɔrtə ˈriːkoʊ/), officially the Commonwealth of Puerto Rico (Spanish: "Estado Libre Asociado de Puerto Rico") — literally Associated Free State of Puerto Rico —, is a self-governing unincorporated territory of the United States located in the northeastern Caribbean, east of the Dominican Republic and west of the Virgin Islands. Puerto Rico is composed of an archipelago that includes the main island of Puerto Rico and a number of smaller islands and keys, the largest of which are Vieques, Culebra, and Mona. The main island of Puerto Rico is the smallest by land area and second smallest by population among the four Greater Antilles, which also include Cuba, Hispaniola, and Jamaica.

Puerto Ricans often call the island Borinquen, from Borikén, its indigenous Taíno name. The terms boricua and borincano derive from Borikén and Borinquen respectively, and are commonly used to identify someone of Puerto Rican heritage. The island is also popularly known as "La Isla del Encanto", which translated means "The Island of Enchantment."

The history of the archipelago of Puerto Rico before the arrival of Christopher Columbus is not well known. What is known today comes from archaeological findings and early Spanish accounts. The first comprehensive book on the history of Puerto Rico was written by Fray Iñigo Abbad y Lasierra in 1786, 293 years after the first Spaniards arrived on the island.