How many letters does the largest alphabet in the world consist of?

The Khmer alphabet or Khmer script is an abugida (alphasyllabary) script used to write the Khmer language (the official language of Cambodia). It is also used to write Pali in the Buddhist liturgy of Cambodia and Thailand. The Khmer alphabet is the longest alphabet in the world, consisting of 74 letters.

The Khmer alphabet was adapted from the Pallava script, which ultimately descended from the Brahmi script, which was used in southern India and South East Asia during the 5th and 6th centuries AD. The oldest dated inscription in Khmer was found at Angkor Borei District in Takéo Province south of Phnom Penh and dates from 611 AD. The modern Khmer script differs somewhat from precedent forms seen on the inscriptions of the ruins of Angkor. The Thai and Lao scripts are descendants of an older form of the Khmer script.

Khmer is written from left to right. Words within the same sentence or phrase are generally run together with no spaces between them. Consonant clusters within a word are "stacked", with the second (and occasionally third) consonant being written in reduced form under the main consonant. Originally there were 35 consonant characters, but modern Khmer uses only 33. Each character represents a consonant sound together with an inherent vowel, either â or ô; in many cases, in the absence of another vowel mark, the inherent vowel is to be pronounced after the consonant.