In the traditional Devanagari transliteration scheme, many words and names have a final "a" appended to them, derived from the original Sanskrit. This "a" is still pronounced in modern Sanskrit derived Indian languages, however it is often more of an "uh" sound than an entirely additional syllable. In Sanskrit, measures of the length of syllables were made in strokes. The long "aa" ('far')sound has two measures, the short "a" ('put') one, and the half 'a' (the short syllable after the 't', sounding like 'uh', in 'cut'). Thus, for most Indians speaking modern languages that derive sound structures from Sanskrit such as Hindi, Bengali or Gujarati, transliterations often omit the final "a" resulting in alternative spellings for many Sanskrit words and names. In these cases, Wikipedia uses the spelling with the appended "a", as it continues to be more common in writing even though it is inconsistent with common pronunciation of many modern languages. This is especially so with many names and terminologies of Hinduism (e.g. Rama/Ram, Mahabharata/Mahabharat, Siva/Shiva/Shiv, etc).
Where the letter "h" appears after a plosive consonant in Devanagari transliteration, it always indicates aspiration, thus "ph" is pronounced as the p in "pit" (with a small puff of air released as it is said) never as the ph in "photo". On the other hand "p" is pronounced as the p in "spit" with no release of air. Similarly "th" is an aspirated "t", neither the th of "this" or the th of "thin".
Devanagari is a form of alphabet called an abugida, as each consonant has an inherent vowel (a), that can be changed with the different vowel signs.
All the vowels in Devanagari are attached to the top or bottom of the consonant or to an AA vowel sign attached to the right of the consonant, with the exception of the I vowel sign, which is attached on the left.
In the Devanagari vowel table below, the "Letter" column contains the symbol used when a vowel occurs without a consonant, the "Vowel sign" column contains the symbol used when a vowel is attached to a consonant, and the "Vowel with [p]" column show an example of the vowel symbol, attached to the "p" consonant.
Devanagari is a script used to write some Indian languages, inclucing Hindi, Sanskrit and Marathi, as well as Nepali.
Devanagari is partly phonetic in the sense that a word written in it can only be pronounced in one way, but not all possible pronunciations can be written perfectly.
Note: Unicode support is required to display these fonts, which may be found here (http://www.alanwood.net/unicode/fonts.html#devanagari).