I've been watching Voyager and the question of how the universal translator works came to me. Voyager is 70K light years from the Alpha Quadrant and is thus encountering aliens that the Federation is unaware of (at least until the Borg or Q). However, Voyager's crew are able to easily communicate with these new species. Now my understanding of the universal translator is that it only translates programmed languages. We have seen where it doesn't work with unknown aliens (TOS Arena and TNG Darmok come to mind) and even common alien languages (Klingon in ST VI, which is odd considering the crew prior to that never had any problems understanding the Klingons). If we assume this, than Voyager should not be able to communicate with these newly discovered aliens in the Delta Quadrant. On the other hand if the universal translator acts as a sort of deciphering program of languages (e.g say based on tone) than Voyager would be able to communicate in some fashion with new species. However, I suspect that there would still be some kind of delay as translators between Voyager and the alien deciphered the language. I have not seen any kind of delay in question and response. So that being said, what is and how does the universal translator work?