Phonemic orthography

A phonemic orthography is a writing system where the written graphemes correspond to phonemes, the spoken sounds of the language. These are sometimes termed true alphabets, but other writing systems, like syllabaries, can be phonemic as well.

Languages with a good grapheme-to-phoneme correspondence include Bulgarian, Basque, Finnish, Georgian, Korean, Sanskrit, Croatian and Serbian. Many constructed languages such as Esperanto and Lojban have phonemic orthographies.

Phonetic alphabets such as International Phonetic Alphabet aim to describe pronunciation in a standard, phonemic, form. They are often used to solve ambiguities in the spelling of written language. They may also be used to write languages with no previous written form.

As dialects of the English language vary significantly, it would be difficult to create a phonemic orthography that encompassed all of them. However, it is fairly easy to create one based on a standard accent such as Received Pronunciation. This would, however, exclude certain sound differences found in other accents, such as the bad-lad split in Australian English. With time, pronunciations change and thus in order to maintain a phonemic orthography such a system would need periodic updating in order to not become out of date, as has happened to English and French.

Difference from phonetic orthographies
Phonemic orthographies are different from phonetic orthographies; whereas in a phonemic orthography, allophones will be represented by the same grapheme, a phonetic orthography would demand that the phonetically distinct allophones be written as such. To take an example from American English: the /t/ sound in the words "table" and "cat" would, in a phonemic orthography, be written with the same character; however, a phonetic orthography would make a distinction between the aspirated "t" in "table", the flap in "butter", the unaspirated "t" in "stop" and the glottalized "t" in "cat" (not all these allophones exist in all English dialects). In other words, the sound that most English speakers think of as /t/ is really a group of sounds, all pronounced slightly differently depending on where they occur in a word. A perfect phonemic orthography has one letter per group of sounds (phoneme), but has different letters where the sounds distinguish words (so "bed" is spelled different from "bet").

A phonetic orthography represents phones, the sounds humans are capable of producing, many of which will often be grouped together as a single phoneme in any given natural language, though the groupings vary across languages. English, for example, does not distinguish between aspirated and unaspirated consonants, but other languages, like Bengali and Hindi, do.