There’s a certain kind of map found all over the Internet that drives me nuts. It’s the map that compares two geographic regions by labelling one with the other: show that this U.S. state has the same GDP as that country by labelling with that country (or better yet, its flag). But the comparisons can get awfully recondite: labelling the Brazilian state of Rio Grande do Sul with Zimbabwe’s flag because they have similar populations is cute but ultimately useless, unless you have some familiarity with both Rio Grande do Sul and Zimbabwe. They’re bad maps because they’re not really informative—they’re just showing off.

But the problem isn’t necessarily the format. For an exception to the above, see TimeOut London’s maps of London. The first map (above) shows London’s population size by illustrating how many other cities’ populations could be crammed inside London’s boundaries; the same is done with greater metropolitan areas, U.S. cities, Scotland and Wales, and other countries. These maps work because a British-based reader will have some sense of what’s being compared to London: they’re not, in other words, esoteric comparisons. [via]