It’s a very ancient technique: most likely the first map was drawn with a stick in the dirt to show the next caveman where to find a decent shelter for himself and his family. Then in the course of time this technique evolved to true art: starting from a crude (and not necessarily accurate) drawing of a small piece of known land it yielded to the temptation of depicting a whole country, the seven seas, the entire world… and who cares if here and there fantasy must take over to fill the blanks? 🙂