Quranic orthography

diacritic used in the Arabic script

thumb|500px|Early written Arabic used only rasm (in black). Later Arabic added diacritics (examples in red) so that homographic consonants, for example these two letters , could be distinguished. Short vowels are indicated by harakat diacritics (examples in blue) which is used in the Qur'an but not in most written Arabic.

form of the Arabic letter alif, written as a short vertical stroke on top of another letter; indicates a long /aː/ sound; e.g. هٰذَا hādhā, رَحْمٰن raḥmān