What are diaeresis?

  • (noun): A diacritical mark (two dots) placed over a vowel in German to indicate a change in sound.
    Synonyms: umlaut, dieresis

Some articles on diaeresis:

Romance Languages - Writing Systems - Diacritics
... Some minority Romance languages use an umlaut (diaeresis mark) in the case of ä, ö, ü to indicate fronted vowel variants, as in German ... pronounced apart, this is often indicated with a diaeresis mark on the vowel ... French also uses the diaeresis on the second of two adjacent vowels to indicate that both are pronounced separately, as in Noël "Christmas and haïr "to hate" ...
List Of Unicode Characters - Greek and Coptic
... Question Mark U+0384 ΄ Greek acute accent U+0385 ΅ Greek diaeresis with acute accent U+0386 Ά Greek Capital Letter A with acute accent U+0387 · Greek Ano Teleia U+0388 Έ Greek Capital ...
List Of XML And HTML Character Entity References - Character Entity References in HTML
... sign uml ¨ U+00A8 (168) HTML 3.2 HTMLlat1 ISOdia diaeresis (= spacing diaeresis) see Germanic umlaut copy © U+00A9 (169) HTML 3.2 HTMLlat1 ISOnum copyright symbol ...