(covers information from Imperial Commonwealth of Planets)
Commonwealth Standard, also referred to as Standard Tongue or Earth Basic, is the dominant de facto state language of the Imperial Commonwealth of Planets. The source of this language is English, a Germanic language originating from the British Isles. This language was the lingua franca of Earth from the late 20th century onward, and when United Earth became more involved in galactic politics, it became the lingua franca of the Alpha Quadrant and the Federation (it was called Federation Standard during this time period). When the Federation collapsed, the language remained, but it was renamed to Commonwealth Standard following the formation of the Commonwealth, to further emphasize the agenda now adopted by the new government.