The Khmer script (អក្ខរក្រមខេមរភាសា; âkkhârâkrâm khémârâ phéasa, informally aksar Khmer; អក្សរខ្មែរ) is used to write the Khmer language which is the official language of Cambodia.
It is generally thought that the Khmer script developed from the Pallava script of India. The oldest dated inscription in Khmer was found at Angkor Borei in Takev Province south of Phnom Penh and dates from 611 AD. Those inscriptions that have survived are engraved in stone and the evolution of Khmer script is as follows:
The Khmer alphabet has fewer symbols for vowels than the language has vowel phonemes. To account for this, each consonant belongs to one of two series, and the vowel produced depends on which series the consonant belongs to (making it an abugida rather than a true alphabet). Therefore, most vowel signs have two possible pronunciations, depending on which series the consonant belongs to. When no vowel sign is present, usually the inherent vowel of the consonant is used. Vowels signs can be divided into two groups: dependent vowel signs, which are written around a consonant letter, and independent vowel letters, which can stand alone. Dependent vowel signs are used more frequently than independent vowels and all independent vowel letters can be phonetically rendered with a dependent vowel. Khmer also has a number of diacritics, which can change the series of the consonant or change the pronunciation of the vowel. Its directionality is horizontal left-to-right, like the Latin alphabet.