Hindustani orthography

Hindustani (Standard Hindi and Urdu) has been written in several different scripts. Most Hindi texts are written in the Devanagari script, which is derived from the Brāhmī script of Ancient India. Most Urdu texts are written in the Urdu alphabet, which comes from the Persian alphabet. Hindustani has been written in both scripts. In recent years the Latin script has been used in these languages for technological or internationalization reasons.

The Devanagari script is an abugida, as written consonants have an inherent vowel, which in Standard Hindi is a schwa. In certain contexts, such as at the end of words, there is no vowel, a phenomenon called the schwa syncope. Other vowels are written with a diacritic on the consonant letter. Devanagari is written from left to right, with a top-bar connecting the letters together.

क्ष kṣ is pronounced /kʃ/ and ज्ञ jñ is /ɡj/.

The schwa (अ or 'ə', sometimes written 'a') implicit in each consonant of the Devanagri script is "obligatorily deleted" in Hindi at the end of words and in certain other contexts. This phenomenon has been termed the "schwa syncope rule" or the "schwa deletion rule" of Hindi. One formalization of this rule has been summarized as ə -> ø | VC_CV. In other words, when a vowel-preceded consonant is followed by a vowel-succeeded consonant, the schwa inherent in the first consonant is deleted. However, this formalization is inexact and incomplete (i.e. sometimes deletes a schwa when it shouldn't or, at other times, fails to delete it when it should), and can yield errors. Schwa deletion is computationally important because it is essential to building text-to-speech software for Hindi.

As a result of schwa syncope, the correct Hindi pronunciation of many words differs from that expected from a literal rendering of Devanagari. For instance, राम is Rām (incorrect: Rāma), रचना is Rachnā (incorrect: Rachanā), वेद is Véd (incorrect: Véda) and नमकीन is Namkeen (incorrect Namakeena).

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