Psi (letter) Psi (letter) Psi (; uppercase ', lowercase '; "psi" ) is the 23rd letter of the Greek alphabet and has a numeric value of 700. In both Classical and Modern Greek, the letter indicates the combination /ps/ (as in English word "lapse"). For Greek loanwords in Latin and modern languages with Latin alphabets, psi is usually transliterated as "ps". The letter's origin is uncertain. It may or may not derive from the Phoenician alphabet. It appears in the 7th century BC, expressing /ps/ in the Eastern alphabets, but /kʰ/ in the Western alphabets (the sound expressed by Χ in the
Letter (alphabet) text than serif faces. Without serifs, an uppercase "I" () is indistinguishable from a lowercase "l" (). The average distribution of letters, or the relative frequency of each letter's occurrence in text in a given language, can be obtained by analyzing large amounts of representative text. This information can be useful in cryptography and for other purposes, such as song lyrics. Letter frequencies vary in different types of writing. Letter (alphabet) A letter is a grapheme (written character) in an alphabetic system of writing. It is a visual representation of the smallest unit of spoken sound. Letters broadly correspond to