Tai Dam alphabet

Origin

The origins of the Tai Dam alphabet are unknown, though the shapes
of the letters suggest that they might have been modelled on the Lao
and/or Thai alphabets. Alternative writing systems, including some based
on the Latin alphabet, are also used to write
Tai Dam.

Notable features

Type of writing system: alphabet
Direction of writing: left to write in horizontal lines
Each consonant letter has a high and low form, which combined with
the presence or absence of the two tones marks, is used to indicate
the six tones of the Tai Dam language.
The high consonants are also used for the syllable final letters:
-w, -y, -m, -n and -ng. The syllable final -k is written with the low
letter k.
Vowels are indicated using diacritics which appear above, below or
to the left and/or right of the consonant letters.
There is no standard order for the consonants, instead each scribe
uses his own order.

Used to write:

Tai Dam, or Black Tai/Tai Noir, a Tai-Kadai language closely related
to Lao and Thai
which is spoken by around half a million people in north-western Vietnam
and northern Laos. There are also Tai Dam speakers in Yunnan province of
China, and in parts of northeastern and central Thailand, where they are
known as Lao Song or Lao Song Dam.