Heta is a conventional name for the historical
Greek alphabet letter
Eta (Η) and several of its variants, when used in their original function of denoting the consonant /h/. The letter Η had been adopted by Greek from the
Phoenician letter
Heth () originally with this consonantal sound value, and
Hēta was its original name. The
Italic alphabets, and ultimately
Latin, adopted the letter H from this Greek usage. However, Greek dialects progressively lost the sound /h/ from their phonological systems. In the
Ionic dialects, where this loss of /h/ happened early, the name of the letter naturally changed to
Ēta, and the letter was subsequently turned to a new use denoting the long
half-open sound. In this function it later entered the classical orthography adopted across the whole of Greece. In dialects that still had the /h/ sound as part of their phonological systems, including early
Athens, the same letter continued to be used in its consonantal function. Just like vocalic Eta, it could occur in a number of glyph variants in different local varieties of the alphabet, including one shaped like a square "8" similar to the original Phoenician (), but also a plain square (), a crossed square (), shapes with two horizontal () or with diagonal bars ().