Mercator projection is by far the most well known map projection in the world. The regular joe or plain jane might not be familiar with such fancy terminology but when presented with the map itself, they'll likely recognize it. That's because the Mercator projection is used everywhere. If you attended an American public school before 1991, the maps in your textbooks or on the walls all used Mercator projection. But maybe that wasn't the best idea.
That's because Mercator projection skews the size of countries and landmasses. Whole generations of people grew up thinking that Greenland was bigger than Africa, that Alaska was about the same size as Brazil, and that Antarctica was the largest continent. In reality, Africa's area is 14 times greater than Greenland's, Brazil is about the size of 5 Alaskas, and Antartica is actually just the 5th largest continent. You can see for yourself with this nifty tool.
Maps using Mercator projection don't portray the real sizes of most areas, that's true, but they offer some specific advantages for navigation. Namely, Mercator projection preserves angles and makes it easier to follow a course of true direction. That's why the majority of today's most popular digital map services, including Google Maps, OpenStreetMap, and Waze, all use Mercator projection (or a variant of it) in their own maps. They all help people get to where they want to go, whether it's their hostel in an unfamiliar city or just the hot new fried chicken sandwich joint across town. Come to think of it, maybe using Mercator projection in schools wasn't such a bad idea after all. Because most people end up using maps just for navigation anyway.