All of the map projections that are practical for usage, thus are mass produced, have a particular distortion. There are maps that are accurate and without distortions but they are not practical for usage because of their shape.
The Mercator map projection is one of the most used around the world. This map projection though is distorting spatial relationships. It is fully accurate on the Equator, but as the projection moves further south and north, it starts to distort, with the distortion being the greatest and the North Pole and South Pole. This results in the areas that are further away from the Equator to be represented as much larger than what they actually are.
Two examples of the distortion of spatial relationships are Greenland and Antarctica. Greenland is an island in the higher latitudes in the Northern Hemisphere, and while the island is big, it actually appears on the maps almost the size of Africa, though Africa is 15 times larger than it. Antarctica is the continent on and around the South Pole. Its distortion is so big, that Antarctica appears on this map projection as by far the largest continent, despite that being very far from the true size of it.
