The Latin letter 'E' differs little from its source, the Greek letter epsilon, 'E'. This in turn comes from the Semitic letter he, which has been suggested to have started as a praying or calling human figure (hillul 'jubilation'), and was probably based on a similar Egyptian hieroglyph that indicated a different pronunciation. In Semitic, the letter represented /h/ (and /e/ in foreign words); in Greek, he became the letter epsilon, used to represent /e/. The various forms of the Old Italic script and the Latin alphabet followed this usage.
Although Middle English spelling used e to represent long and short /e/, the Great Vowel Shift changed long /e/ (as in 'me' or 'bee') to /i/ while short /e/ (as in 'met' or 'bed') remained a mid vowel. In other cases, the letter is silent, generally at the end of words.