Gerard Mercator was a Flemish cartographer, geographer, and mathematician born in 1512. He is best known for creating the Mercator projection, a cylindrical map projection that allows for accurate navigation by preserving angles. This innovation made it easier for sailors to plot their courses across the oceans. Mercator's work significantly influenced the field of cartography and navigation. His maps were widely used during the Age of Exploration, helping explorers and traders navigate uncharted territories. He also contributed to the understanding of geography through his detailed world maps and globes, which were groundbreaking for their time.