When writing English we use the 26 letters of the alphabet. However, when speaking there are roughly 46 different sounds in English. These sounds are called phoneme. If you ' re concentrating on the sounds in English, you need 46 characters to represent them all. One way of doing this is to use the ' phonemic alphabet ' , which has some extras characters to represent the sounds in English for which there is no clear equivalent letter or letters
. You can use phonemes to write out the pronunciation of words and in any dictionaries for English learners you will see the pronunciation written out. To show that what is written is phonemes (sounds ) and not letters, phonetic transcriptions are written between slash.