The two basic elements of the code are the phoneme and the grapheme . The phoneme is the smallest unit of sound which distinguishes one word from another. The phoneme is a speech sound. The grapheme is the written representation of the phoneme, or the smallest unit of sound presented in written form. The grapheme is composed of the symbols we use to picture the sound on paper.
Graph refers to drawn, written, or recorded.
A grapheme my consist of more than one letter, representing the phoneme. A letter and a grapheme are not the same thing. American English contains only 26 letters, but has 44 separate phonemes or speech sounds. Some symbols and patterns are consistent and reliable, making phonics or word recognition skills easier to develop. The most reliable of the 26 letters of the alphabet are the consonants.