The mythology of Firefly is deep and immersive, pulling the viewer into understanding and empathizing with the characters while still being dazzled by the science fiction world surrounding them. Like many of Joss Whedon's other series, the mythology of the series is an extremely important component the writing process. This page takes an indepth look at various parts of the Firefly mythos.
An interesting way that Firefly differs from many current and past sci-fi series is in the lack of alien races. This was demonstrated in The Message, where on a space station/open market, a man advertises "Proof that alien races exist and are living among us". The doctor identifies the proof as nothing more than a cow fetus.
Throughout the series, the characters speak short bursts of Chinese, usually when under stress or angry. The reason for this is that China and the United States, by the end of life on "Earth-That-Was", were the only superpowers left. Because of this, everybody is effectively bi-lingual (most likely by picking it up 'on the street' rather than through formal education). The particular version of Chinese used is a combination of Mandarin and modern slang.