Not mentioned in the article, Hangul (the Korean alphabet) was created in 1443 by the King. It was meant to aid literacy because of the preexisting incompatibility of Chinese characters and the Korean spoken language. It's actually surprisingly easy to learn - you could do it in a really short time. But, because the symbols (24 of them) represent sound only, you won't usually know what you're saying.
Also, it was designed with a certain concept in mind: "The letters for the five basic consonants reflect the shape of the speech organs used to pronounce them, and they are systematically modified to indicate phonetic features"
To be exact, Hunminjeongeum (훈민정음) is what the King Sejong actually created. It is, in addition to the stated goal, thought to be the ultimate linguistic geekery by the King because one of the first books printed in Hunminjeongeum was Dongguk Jeongun [1], which set out to standardize the "orthodox" Chinese pronunciation in Korea. As always that didn't go well; the book does tell a lot about the Middle Korean despite of its failure.
i learned hangul characters by reading street signs while travelling through south korea. most signs were both in hangul and latin characters.
then i found a keyboard typing practice program where i patched the letter images and replaced them with the appropriate hangul character parts, to practice typing.
this skill came in handy when i needed to write down some korean words when hearing them.
Also, it was designed with a certain concept in mind: "The letters for the five basic consonants reflect the shape of the speech organs used to pronounce them, and they are systematically modified to indicate phonetic features"
https://en.m.wikipedia.org/wiki/Hangul