Hangul consists of 40 letters. It has 21 vowels and 19 consonants; among these 40 letters, 24 are the basic letters while the other 16 are compounds formed from the basic letters.

Vowels When you write a vowel which does not have syllable consonant, you must write the consonant 'ㅇ'. In this case, 'ㅇ' is a null consonant which merely indicates the absence of a syllable-initial consonant.   Simple vowel   ㅏ,ㅓ,ㅗ,ㅜ,ㅡ,ㅣ,ㅐ,ㅔ   Diphthongs   ㅑ,ㅕ,ㅛ,ㅠ,ㅖ,ㅒ,ㅘ,ㅙ,ㅝ,ㅞ,ㅚ,ㅟ,ㅢ

Consonants In Korean, the consonant is always pronounced in combination with a vowel. However, each consonant has its own name. There are some examples to present consonant sounds.   Plain consonants   ㄱ,ㄴ,ㄷ,ㄹ,ㅁ,ㅂ,ㅅ,ㅇ,ㅈ     Aspirated consonants   ㅋ,ㅌ,ㅍ,ㅊ,ㅎ     Glottalized consonants   ㄲ,ㄸ,ㅃ,ㅆ,ㅉ