Dhivehi is an
Arabic influenced
abugida writing system among the people of
Maldives. It was first attested in documents from 1200
CE. In common use until the seventeenth century, it was supplanted by
Thaana, which retained the letter shapes but reversed order to match with
Arabic; right to left. The script possesses 24 consonant characters. The first nine bear a striking similarity to Arabic numerals (not those used by
Western languages, but the original Arabic numerals). The next nine come from a local numeral system used during the earlier history of the island. The final characters are used mainly for transcribing
loan words from
Persian and Arabic and share similarity with the Arabic
abjad.
All consonants in Dhivehi are marked with a diacritic. There are ten diacritics for vowels; five for short vowels and five for long vowels. Long vowels are most often represented by doubling the diacritic for the matching short vowel. An eleventh diacritic marks a consonant with no associated vowel sound following it. An empty consonant is used to write word-initial vowel sounds and with the empty vowel sign marks a glottal stop. A special consonant character with empty vowel sign that normally marks word-end glottal stops will double any consonant it precedes. Doubled nasals do not use this method, but rather are preceded by an 'n' with empty vowel sign. Diphthongs are formed by writing the second vowel independently with the empty consonant marker. Overall the abugida is extremely phonetic and precise in its transcription of the Maldives language.
Daniels, Peter T., Bright William. The World's Writing Systems. Oxford: Oxford University Press, 1996.