The Age of Discovery also known as the Age of Exploration, part of the early modern period and largely overlapping with the Age of Sail, was a period from approximately the 15th century to the 17th century, during which seafarers from a number of European countries explored, colonized, and conquered regions across the globe. The Age of Discovery was a transformative period in world history when previously isolated parts of the world became connected to form the world system and laid the groundwork for globalization. The extensive overseas exploration, particularly the European colonization of the Americas, with the Spanish and Portuguese, and later the British, at the forefront, spurred global trade. The interconnected global economy of the 21st century has its roots in the expansion of trade networks during this era.