U+0EC4 Lao Vowel Sign Ai

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Lao script or Akson Lao (Lao: ອັກສອນລາວ [ʔák.sɔ̌ːn láːw]) is the primary script used to write the Lao language and other minority languages in Laos. Its earlier form, the Tai Noi script, was also used to write the Isan language, but was replaced by the Thai script. It has 27 consonants (ພະຍັນຊະນະ [pʰā.ɲán.sā.nāʔ]), 7 consonantal ligatures (ພະຍັນຊະນະປະສົມ [pʰā.ɲán.sā.nāʔ pā.sǒm]), 33 vowels (ສະຫລະ/ສະຫຼະ [sā.láʔ]), and 4 tone marks (ວັນນະຍຸດ [wán.nā.ɲūt]).

The Lao abugida was adapted from the Khmer script, which itself was derived from the Pallava script, a variant of the Grantha script descended from the Brāhmī script, which was used in southern India and South East Asia during the 5th and 6th centuries AD. Akson Lao is a sister system to the Thai script, with which it shares many similarities and roots. However, Lao has fewer characters and is formed in a more curvilinear fashion than Thai.

Lao is written from left to right. Vowels can be written above, below, in front of, or behind consonants, with some vowel combinations written before, over, and after. Spaces for separating words and punctuation were traditionally not used, but space is used and functions in place of a comma or period. The letters have no majuscule or minuscule (upper- and lowercase) differentiation.