Gerardus Mercator published his world map in 1569 with one purpose: a straight line drawn on it is a line of constant compass bearing, which is exactly what a navigator wants. The cost is area. Stretching the meridians to keep angles true inflates everything far from the equator, which is why Greenland looks the size of Africa on a wall map that was designed for a ship.
Why this oneEvery argument about world maps being wrong begins here.