“There are 24 basic letters and digraphs in 한글” (Hangul) says Talk To Me In Korean Workbook Level 1. I wondered, what’s a digraph?
Digraph – pair of characters used to make one sound (phoneme)
digraphs are letters and diphthongs are sounds.
A digraph is two letters that spell one sound.
An example of digraph in English is ph. Examples of Korean digraphs are ㅒ, ㅖ, ㅚ, ㅃ, and ㅆ.
Vowel sounds made with one pure sound and no tongue movement are called monophthongs 단모음 (mono meaning “one” and phthong meaning “sound”). Of the vowels, there are 8 monothongsㅏ ㅓ ㅗ ㅜ ㅡ ㅣ ㅐ ㅔ.
A diphthong 이중모음 is one sound formed by the combination of two vowel sounds. When you are saying a diphthong, you are producing one sound by saying two vowels. Therefore, your tongue and mouth glide from one letter to the next to create one sound. Of the vowels, there are 13 diphthongs: ㅑ ㅕ ㅛ ㅠ ㅒ ㅖ ㅘ ㅝ ㅙ ㅞ ㅚ ㅟ ㅢ.
14 letters are consonants. Delving into Wikipedia to learn what a digraph is led me to a description of “muddy” consonants (slack voice). It is a description of how much air gets through the glottis when making the consonant sound.
Voicing occurs when air is expelled from the lungs through the glottis. As the vocal folds vibrate, the resulting vibration produces a “buzzing” quality to the speech. If the vocal chords are completely relaxed, you get maximum airflow and the chords do not vibrate. This is called “voiceless”. The range from open to closed is described below.