By is English, via is Latin. They're essentially synonyms, though "via" is a bit more refined/educated/pretentious (choose whichever suits your personal bias according to how you feel about the person using it). Via can also mean "way" or "street."

Hi, Petch! "Via" has two main meanings: 1) through a place. example: I flew from Rome to London via Paris. 2) by means of, by ways of. ex: via air mail. ex: I heard about Alex's marriage via Jason.

Via - a way to do something How do you go to work? - Via train How do you send a letter to a friend - Via post