Obsolete Hangul jamo
The Korean alphabet, known as Hangul internationally, Hangeul in South Korea, and Choson'gŭl in North Korea, was introduced with 28 main letters, which are called jamo. Other extended vowels and consonants also existed or were later introduced but faded from use. Now, 24 main letters are in use for modern Korean.
A number of letters that became obsolete for Korean have previously and even currently seen use for other languages. For example, ㆍ is obsolete for Korean but used for the Jeju language.
Many obsolete letters and combinations are accounted for in Unicode.