As a Brahmic abugida, the fundamental principle of Devanagari is that each letter represents a

consonant, which carries an inherent schwa vowel. This is usually written in Latin as a, though it is represented as [ə] in the International Phonetic Alphabet.[5] The letter क is read ka, the two letters कन are kana, the three कनय are kanaya, etc. Other vowels, or the absence of vowels, require modification

of these consonants or their own letters:

A final consonant is marked with the diacritic  �्, called the virāma in Sanskrit, halant in Hindi, and

occasionally a "killer stroke" in English. This cancels the inherent vowel, so that from क्नय knaya is

derived क्नय� knay. The halant is often used for consonant clusters when typesetting conjunct

ligatures is not feasible.

Consonant clusters are written with ligatures (saṃyuktākṣara "conjuncts"). For example, the three consonants क� , न�, and य�, (k , n, y), when written consecutively without virāma form कनय, as shown

above. Alternatively, they may be joined as clusters to form क्नय knaya, कन्य kanya, or

क्न्य knya. This system was originally created for use with the Middle Indic languages, which have

a very limited number of clusters (the only clusters allowed are geminate consonants and clusters

involving homorganic nasal stops). When applied to Sanskrit, however, it added a great deal of

complexity to the script, due to the large variety of clusters in this language (up to five consonants,

e.g. rtsny). Much of this complexity is required at least on occasion in the modern Indo-Aryan

languages, due to the large number of clusters allowed and especially due to borrowings from

Sanskrit. Vowels other than the inherent a are written with diacritics (termed matras). For example, using

क ka, the following forms can be derived: क  ke, क  ku, क� kī, क� kā, etc.

For vowels as an independent syllable (in writing, unattached to a preceding consonant), either at

the beginning of a word or (in Hindi) after another vowel, there are full-letter forms. For example, while the vowel ū is written with the diacritic  ् in क  kū, it has its own letter ऊ in ऊक ūka and (in

Hindi but not Sanskrit) कऊ kaū.

Such a letter or ligature, with its diacritics, is called an akṣara "syllable". For example, कनय kanaya is

written with what are counted as three akshara, whereas क्न्य knya and क  ku are each written with one.

As far as handwriting is concerned, letters are usually written without the distinctive horizontal bar,

which is added only once the word is completed.[6]