A grapheme is the smallest functional unit of a writing system in linguistics. It is a written symbol that represents a sound, which can be a single letter or a sequence of letters. Graphemes are abstract concepts and similar to the notion of a character in computing. A specific shape that represents any particular grapheme in a given typeface is called a glyph. There are multiple graphemes that can represent one phoneme, and one sound can have many different spellings or graphemes.
For example, the letter t' is a grapheme that represents the sound /t/ . The word "tap" consists of three graphemes: t, a, and p, while the word "trap" consists of four graphemes: t, r, a, and p. Graphemes are used in reading by attaching a verbal sound to every given grapheme, and in writing to attach a written symbol to each sound in the words they are writing.
