The Lao script, known as “akson lao” (ອັກສອນລາວ), is a unique alphasyllabic writing system that has its origins in the Khmer alphabet, itself derived from the Brahmi script of ancient India. Its historical development dates back to the 13th century, under the reign of King Fa Ngum, founder of the Lan Xang kingdom. The Lao alphabet has evolved over time, taking on more rounded forms and adapting to the specific linguistic and cultural needs of Laos. This writing system is distinguished by several unique features: it has no capital letters, uses no specific punctuation, and words are generally spelled as they are pronounced, making it easier to learn pronunciation from the written form. The Lao alphabet comprises 38 consonants, although some sources mention 33 consonants (27 basic consonants and 6 compound consonants). These consonants are divided into three distinct tonal classes: 8 medium consonants, 13 low consonants and 13 high consonants, a crucial classification for the tonal pronunciation of Lao words.

The syllable structure of Lao is mainly based on the consonant-vowel (CV) model, although more complex structures such as consonant-vowel-consonant (CVC) are also present. Each syllable generally begins with a consonant, followed by a vowel, and may end with a consonant. The Lao writing system reflects this syllabic structure, with characters representing consonants accompanied by an inherent vowel, which can be modified by additional diacritics. The 27 vowels of the Lao alphabet are placed in various positions in relation to the consonants - before, after, above or below - depending on the specific vowel, which is a distinctive feature of this script. This spatial arrangement of vowels, combined with the tonal nature of the language (where tones are not always explicitly marked in the script), contributes to the complexity and uniqueness of the Lao script. Mastery of these elements is essential to understanding and correctly using the Lao writing system, which plays a central role in the preservation and transmission of Lao culture and literature.