The twenty-eight letters of the Hangeul alphabet—seventeen consonants and eleven vowels—were created in 1443. The form of each consonant reflects the shape of the vocal organs when pronouncing that letter. The vowels are configurations of three primary vowels representing the three elements of the universe: the sky, the earth, and humanity. By combining these twenty-eight letters into syllabic blocks, it is possible to transcribe any sound in the Korean language. While the letters represent a meticulously organized system based on phonology, anatomy, neo-Confucianism, and other theoretical principles, their simple shapes and sounds are amazingly easy to learn. For its unique qualities and scientific value, Hangeul is greatly esteemed by linguists around the world.