Unlike English alphabet, Korean alphabet is invented. When Korean alphabet was invented, there was some thought behind the shape of them.
http://koreanletter.net/vowel.html – Vowels Design
http://koreanletter.net/cons.html – Consonants Design
Consonant shapes are designed after the shape of human’s speech organs when you make the sound. Vowel shapes are designed after the symbols for heaven, earth and human.
So all the 11,172 Korean letters are made from 24 alphabets, and 24 alphabets are made from just 8 basis shapes!