EDIT Thaana is written from right to left. It has 24 letters, all consonants, and a number of diacritics and letters for loanwords and Arabic transliterations. Thaana is an abugida, which means certain vowels are associated with the consonants unless diacritics indicate a different vowel.

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EDIT Language
Thaana is used to write the Dhivehi language, spoken by about 300,000 people on the Maldives and on India's Minicoy Islands.

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EDIT History
The origin of Thaana is quite unique. Its first nine characters (v-h) are derived from the Arabic numerals, the next nine (m-d) were the Indic numerals used in the area. The characters after that (z-ch) and those for loanwords are derived from phonetically similar native consonants with the use of diacritics.
The script was developed during the 16th century by an unknown inventor and appeared in government documents for the first time in 1703.

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EDIT Fonts
The Maldivian Internet Task Force (www.mitf.net) offers a font that's free under the GNU Free Documentation Licence.

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