What different world maps get right - and what they get wrong

The UN has just called for the predominant world map to be replaced with one that more accurately reflects the true size of continents like Africa.

The "Correct the Map" resolution adopted by the General Assembly aims to fix the discrepancy on the Mercator map, in which the African continent is shown as being of similar size to Greenland - even though it is in reality about 14 times larger.

It adopted a new map, the Equal Earth projection, which better represents the true sizes of landmasses - but comes with problems of its own.

There have been many prominent attempts over the years to solve the problem of accurately representing the surface of a sphere on a flat rectangle, each with its own benefits and drawbacks.

The now widely used Mercator map was created in 1569 by Flemish cartographer Gerardus Mercator.

Its main purpose was to help European sailors navigate the oceans, as cartography Professor James Cheshire at University London College explained.

"He wanted a straight line to be drawn on a map to look like a straight line in reality if you followed a compass bearing," he told the BBC. "That was what it was intended to do, and that's what it does brilliantly well."

To keep those angles correct on a flat map, Mercator had to stretch the grid lines wider as they moved away from the equator toward the poles.