What was Mercator's profession?

What was Mercator's profession? He was a cartographer. Gerardus Mercator was a 16th-century Flemish mapmaker whose work helped transform European geography and navigation.

Mercator was also a geographer, mathematician, engraver, globe maker, and cosmographer, but “cartographer” is the clearest single answer to this question. He produced maps of Europe, Britain, Palestine, and other regions, often combining geographical research with precise copperplate engraving.

His best-known achievement is the Mercator projection, first published in a world map in 1569. It represents lines of constant compass bearing as straight lines, making the projection especially useful for marine navigation. However, it greatly enlarges landmasses near the poles, so it is not an accurate guide to relative area.

Mercator also helped popularize the word “atlas” for a bound collection of maps. He died in Duisburg in 1594, and his unfinished atlas was published posthumously by his family.