In typography, a homoglyph or homograph is a character shape that is visually identical or nearly identical with another character; the two characters can be said to form a "homograph pair".
For example, in most typefaces the Latin letter 'a' and the Cyrillic letter 'а' are visually identical, as are the Greek letter 'Α' and the Latin letter 'A'. There are also many examples of near-homographs within the same writing system such as 'í' (with an acute accent) and 'i'.
The Unicode character set contains many homographic characters. These present a possible security risk for internationalized domain names by allowing the spoofing of one domain name by another which is a homograph for the first one, thus providing opportunities for various security exploits, most notably phishing attacks. As of 2005, efforts are underway by DNS registries and Web browser designers to minimize or eliminate this risk as far as possible.
Historically, the near-homoglyphs of Y and Þ in old English script has led to the mistaken supposition that the word "The" was formerly written and pronounced as "Ye"
