Every map grapples with making Earth, a spherical planet, appear to scale in two dimensions. But the most well-known version today - called the Mercator projection - drastically distorts the size of many countries.
Few examples demonstrate this distortion better than Greenland. Take a look at the overlay below, submitted on Reddit by user Asuros. The pink shape is Africa, while the purple represents Greenland.
On the Mercator map, shown below, Greenland appears almost the same size as Africa.
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In reality, Greenland only covers about 1/14 of Africa.
Created by Flemish cartographer Gerardus Mercator in 1569, the Mercator projection preserves direction, instead of size, making it useful for navigation. Google Maps, as well as many other online services, use it, and most schools teach it.
Despite its wide use, however, the Mercator projection distorts land masses approaching the poles.
Tissot's indicatrix, a geometric equation used to show distortion on maps, demonstrates the problems with Mercator. Notice the red circles become larger farther north or south of the equator.
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Some may prefer other map projections, like the Gall-Peters, but none can represent world perfectly. Displaying a 3-D shape on a flat surface includes some distortion no matter what.