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**Cartography**, the art and science of mapmaking, was Abraham Ortelius' field of specialization. As a prominent 16th-century Flemish cartographer, Ortelius made significant contributions to the development of modern cartography. His most notable work, the "Theatrum Orbis Terrarum," published in 1570, is considered the first modern atlas and played a pivotal role in shaping the understanding of geography during the Age of Exploration.