Indian Ocean, Equator, Malay Archipelago.
When it comes to archipelagos, as the name implies, it's a large group of islands clustered together. and within the four characters of "Malay Archipelago," the number of islands included is... over twenty thousand.
Under such a vast foundational number, naming these islands became an exceedingly troublesome affair, beginning with proper names, later reduced to mere letters, and eventually, they resorted to algebraic representations such as m1, m2 to hastily cover them. And then... eventually, they didn't even bother with codes.
