Editing Abugida (section)

==General description==
The fundamental principles of an abugida apply to words made up of consonant-vowel (CV) syllables. The syllables are written as letters in a straight line, where each syllable is either a letter that represents the sound of a consonant and its inherent vowel or a letter modified to indicate the vowel. Letters can be modified either by means of [[diacritic]]s or by changes in the form of the letter itself. If all modifications are by diacritics and all diacritics follow the direction of the writing of the letters, then the abugida is not an alphasyllabary. However, most languages have words that are more complicated than a sequence of CV syllables, even ignoring tone.

The first complication is syllables that consist of just a vowel (V). For some languages, a [[zero consonant]] letter is used as though every syllable began with a consonant. For other languages, each vowel has a separate letter that is used for each syllable consisting of just the vowel. These letters are known as ''independent vowels'', and are found in most Indic scripts. These letters may be quite different from the corresponding diacritics, which by contrast are known as ''dependent vowels''. As a result of the spread of writing systems, independent vowels may be used to represent syllables beginning with a [[glottal stop]], even for non-initial syllables.

The next two complications are [[consonant cluster]]s before a vowel (CCV) and syllables ending in a consonant (CVC). The simplest solution, which is not always available, is to break with the principle of writing words as a sequence of syllables and use a letter representing just a consonant (C). This [[Syllable#Coda|final consonant]] may be represented with:
*a modification of the final letter that explicitly indicates the lack of a vowel ([[virama]]),
*a lack of vowel marking on the letter (often with ambiguity between no vowel and a default [[inherent vowel]]),
*vowel marking on the letter for a short or neutral vowel such as ''[[schwa]]'' (with ambiguity between no vowel and that short or neutral vowel), or
*a visually unrelated letter.

In a true abugida, the lack of distinctive vowel marking of the letter may result from the diachronic loss of the inherent vowel, e.g. by [[syncope (phonology)|syncope]] and [[apocope]] in [[Schwa deletion in Indo-Aryan languages|Hindi]].

When not separating syllables containing consonant clusters (CCV) into C + CV, these syllables are often written by combining the two consonants. In the Indic scripts, the earliest method was simply to arrange them vertically, writing the second consonant of the cluster below the first one. The two consonants may also merge as [[Typographic ligature|conjunct consonant]] letters, where two or more letters are graphically joined in a [[Typographic ligature|ligature]], or otherwise change their shapes. Rarely, one of the consonants may be replaced by a gemination mark, e.g. the [[Gurmukhi]] ''[[Gurmukhi alphabet#Gemination|addak]]''.

When they are arranged vertically, as in [[Burmese alphabet|Burmese]] or [[Khmer alphabet|Khmer]], they are said to be 'stacked'. Often there has been a change to writing the two consonants side by side. In the latter case, this combination may be indicated by a diacritic on one of the consonants or a change in the form of one of the consonants, e.g. the [[Devanagari#Conjunct consonants|half forms]] of Devanagari. Generally, the reading order of stacked consonants is top to bottom, or the general reading order of the script, but sometimes the reading order can be reversed.

The division of a word into syllables for the purposes of writing does not always accord with the natural phonetics of the language. For example, Brahmic scripts commonly handle a phonetic sequence CVC-CV as CV-CCV or CV-C-CV. However, sometimes phonetic CVC syllables are handled as single units, and the final consonant may be represented:
*in much the same way as the second consonant in CCV, e.g. in the [[Tibetan alphabet|Tibetan]]{{citation needed|reason=This is the condensed, single-stack style, not the usual multi-stack style|date=January 2016}}, [[Khmer alphabet|Khmer]]<ref name="TUS_Khmer_VC"/> and [[Tai Tham alphabet|Tai Tham]]<ref name=Tai_Tham_Unicode_Proposal/> scripts. <!-- Full stop is **after** reference because the final reference refers only to Tai Tham. The list of names has now been sandwiched by 'the ... scripts' to prevent the reference for Tai Tham being taken to apply to the whole sentence. --> The positioning of the components may be slightly different, as in Khmer and Tai Tham.
*by a special dependent consonant sign, which may be a smaller or differently placed version of the full consonant letter, or may be a distinct sign altogether.
*not at all. For example, repeated consonants need not be represented, homorganic nasals may be ignored, and in [[Baybayin]] and [[Makasar script]], the syllable-final consonant was traditionally never represented.<ref name=WWS_Insular_SEA/><!-- p476 -->

More complicated unit structures (e.g. CC or CCVC) are handled by combining the various techniques above.

'''Examples using the [[Devanagari]] script'''
* ''K'' = /ka/ = [[File:devnag ka.png]]
* ''Ki'' = /ki/ = [[File:devnag ki.png]]
* ''K*'' = /k/ = [[File:devnag k.png]] (with a ''[[Halant]]'' [[File:devnag halant.png]] under the character)
* ''K*M'' = /kma/ = [[File:devnag kma.png]]
* ''İK'' = /ika/ = [[File:devnag ika.png]]
* ''İK*'' = /ik/ = [[File:devnag ik.png]]
* ''İKi'' = /iki/ = [[File:devnag iki.png]]
* etc.