The Balinese script was probably derived from Pallava and Old Kawi alphabets, which ultimately were derived from the Brahmi alphabet, the root of almost all the Indic and Southeast Asian abugidas.
Like most abugidas, each letter has an inherent vowel of /a/. Other vowels are indicated by using diacritics, which can appear above, below, to the left, or to the right of the consonant.