H, which in reference is spelled aitch, is the eighth letter of the latin alphabet.
The Semitic letter ח (Ħęt) probably represented the phoneme /X/ (pharyngeal voiceless fricative) (IPA [ħ]). The form of the letter probably stood for a fence. Early Greek H stood for /h/, but later on &Eta or &eta (Ęta) stood for/. In Modern Greek this phoneme fell together with /i/, similar to the English development where E/ and EE / came to be both pronounce/ . In Etruscan and Latin, the sound value /h/ was maintained, but all Romance languages lost the sound - only Romanian borrowed the /h/ phoneme from its neighbouring Slavic languages and Castilian /x/ developed [h] allophones in some Spanish-speaking countries.
H is also:
- The chemical symbol for hydrogen.
- A symbol for the SI derived unit for electric inductance, the henry
- A musical note in the German system.