Federation Standard

Federation Standard, more commonly referred to as Standard, is the official language of the United Federation of Planets, used in official documents by the Federation government and used as signiage on Federation starships. When the Republic of Bajor joined the Federation in 2376, many signs and directories located throughout the planet were altered to include both Bajoran and Standard directions. (Bajor: Fragments and Omens.)

Federation Standard seems to be English or a derivitive of English, given the English writings seen on the hulls of Federation starships.