Vietnamese language and computers

The Vietnamese language is written with a complex Latin alphabet that requires various accommodations in computing. Historically, Vietnamese was written in a much more complex logographic script, chữ Nôm, which does not yet enjoy full computer support.

There are as many as 46 character encodings for representing the Vietnamese alphabet.Unicode has become the most popular, due to its superior compatibility and software support. Diacritics may be encoded either as combining characters or as precomposed characters, which are scattered among the Latin Extended-A, Latin Extended-B, and Latin Extended Additional blocks. The Vietnamese dong symbol is encoded in the Currency Symbols block. The Middle Vietnamese letter B with flourish (ꞗ) is included in the Latin Extended-D block. The apex is not included in Unicode, but U+1DC4 ◌᷄ COMBINING MACRON-ACUTE may serve as a rough approximation.

Early versions of Unicode assigned the characters U+0340 ◌̀ COMBINING GRAVE TONE MARK and U+0341 ◌́ COMBINING ACUTE TONE MARK for the purpose of placing these marks beside a circumflex, as is common in Vietnamese typography. These two characters have been deprecated; U+0301 ◌́ COMBINING ACUTE ACCENT and U+0300 ◌̀ COMBINING GRAVE ACCENT are now used regardless of any present circumflex.

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